Ultrahigh strength magnesium via solidification of nanocolloid

Ultrahigh strength magnesium via solidification of nanocolloid | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Ultrahigh strength magnesium via solidification of nanocolloid Hari Babu Nadendla, Xinliang Yang, Changming Fang, Shunsuke Nishi, and 8 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7589727/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted You are reading this latest preprint version Abstract We report a simple, scalable route to produce ultrahigh-strength magnesium (Mg) via solidification of a colloidal solution containing nanoscale niobium carbide (NbC) particles suspended in liquid magnesium (Mg(l)). A single-atom-level investigation reveals that NbC exhibits excellent spontaneous wetting with molten Mg, driven by the formation of an ordered layer of Mg atoms strongly bonded to the carbon atoms on the NbC {001} surface. This creates a novel type of Mg-coated NbC (Mg@NbC) particles in liquid Mg and is referred to as Mg(l)-Mg@NbC nanocolloid. This unique and spontaneous wetting behaviour enables uniform nanoparticle dispersion in the molten Mg without external fields, and in the solidified Mg matrix without the need for thermomechanical processing. The resulting NbC dispersoids act as coherent, hard reinforcement phases, significantly strengthening the Mg matrix. As a result, the Mg-NbC material exhibits ultrahigh tensile strength and stiffness, surpassing those of all previously reported Mg alloy systems. Physical sciences/Materials science/Nanoscale materials/Structural properties Scientific community and society/Business and industry/Engineering/Mechanical engineering Figures Figure 1 Figure 2 Figure 3 Figure 4 Full Text Mg has a low density of 1.78 g·cm -3 and a high damping capacity with a loss factor ~11.8×10 -3 (~10 times higher than Al and Steel), and thus offers tremendous potential in achieving lightweight vehicles with improved fuel economy and reduced CO 2 emission. However, the yield strengths of the most used automotive Mg alloys are in the range of 100-200 MPa, which is just nearly half that of Al alloys and 1/4 that of high strength steels; thus, the industry is not fully able to utilise their lightweight potential. Among the major alloy strengthening mechanisms, the uniform dispersion of nanoscale secondary phase precipitates is particularly effective 1 . Alloying additions of rare earth (RE) elements in Mg alloys results in a significant strength improvement due to the effective precipitation of RE-containing phases upon heat treatment 2, 3 . Despite the promise of this approach, the high cost and limited availability of RE elements have historically hindered the widespread use of Mg-RE alloys in industry, with their potential only recently being actively explored 4, 5 . As another strategy, fine-grained magnesium produced through thermomechanical processing is typically combined with precipitation hardening to achieve high strength 6 . However, the resulting microstructures often exhibit limited thermal stability, which compromises their performance under demanding service conditions. Ceramic particles with high shear moduli, as an alternative approach to the in-situ formed precipitates, can serve as the non-deforming particles that favour the Orowan strengthening mechanism 7 . Their strengthening effect depends mainly on particle size and number density. This approach does not require specially tailored alloy compositions or complex thermomechanical processing routes. Reported data on various metallic systems highlight that in addition to ceramic particles contributing to strengthening 8-12 , the resulting nano-sized grain structure of the metallic matrix significantly improves the overall mechanical strength 13, 14 . For example, in Mg alloys, a multi-step external field treatment on molten metal followed by severe plastic deformation were conducted to disperse SiC nanoparticles 13 . In molybdenum alloys, the in-situ reaction of the precursor compounds 14 was utilised to introduce the nano-sized ceramic particles and then a rolling process was conducted to disperse the nanoparticles and refine the Mo grain size. These ceramic phases are thermally stable and can effectively retain their strengthening effect at elevated temperatures 9, 15 . This is also the case of Al incorporated with graphene-coated MgO nanoparticles 9 , via the powder metallurgy route, which showed improved strength and creep resistance at temperatures as high as 500°C. Similarly, non-equilibrium solidification in additive manufacturing was applied to incorporate La 2 O 3 nanoparticles in a medium entropy alloy matrix and demonstrated further enhancement of creep property at 1093°C 15 compared with the pure alloy parent phase. We report here an ultrahigh tensile strength of ~680 MPa in Mg produced by solidification of a Mg colloid containing fine scale NbC dispersions. The excellent wetting characteristics of the NbC phase with molten magnesium enabled the processing of such high strength material. We investigate the fundamental mechanism for the atomic interaction between Mg and NbC using aberration-corrected scanning transmission electron microscopy (STEM) and electron energy loss spectroscopy (EELS). We further perform density functional theory (DFT) calculations to investigate the interfacial interactions and atomic arrangements at the liquid Mg/NbC (Mg(l)/NbC) interfaces, with an emphasis on the non-polar NbC {001} surface that terminates most produced NbC nanoparticles. This study reveals that the formation of an ordered layer of Mg atoms, strongly bonded to the carbon atoms on the NbC {001} surface, results in a novel Mg-coated NbC (Mg@NbC) colloid, which plays a critical role in the observed excellent wetting characteristics. During solidification of the Mg(l)-Mg@NbC colloid, the Mg solidification front spontaneously engulfs the NbC dispersoids into the growing Mg grains. In the resulting solidified alloys, these embedded dispersoids can effectively contribute to strengthening, similar to the role of coherent precipitates in monolithic Mg alloys. Mg-NbC material by solidification of colloidal solution Historically, the preparation of stable high-temperature colloidal solutions via the combination of molten metal and ceramic particulate dispersions has not been possible, due to the poor wettability of the ceramic particles by the molten metal 16 . We have identified the metal-ceramic (Mg-NbC) system as an excellent candidate to realise this task, thanks to perfect wetting characteristics that enable the production of a high-temperature nanocolloidal solution consisting of NbC nano-dispersions in molten Mg using a simple, practical and scalable method. For producing nanocolloidal solutions, we first compressed NbC powders with particle size of 15 nm (NbC nano ), 287 nm (NbC submicron ) and 906 nm (NbC micron ) (see methods for details) into bulk pellets and then infiltrated molten Mg into these compressed pellets at ambient pressure (Fig. 1). The colloidal solution was then solidified using a conventional casting process to obtain the Mg-NbC material that consists of uniform NbC nanodispersoids in the Mg matrix (Supplementary Figs. 1, 2 for the case of the smaller-sized NbC nano particles). During infiltration into the compressed powder pellet, molten Mg wetted the nanoparticles causing them to detach from each other and form a stable nanocolloid (see Supplementary Note). This preparation method significantly simplifies the incorporation of ex-situ ceramic nanoparticles into the molten metal with a uniform dispersion. Similarly, uniform dispersions can also be seen in Mg-NbC submicron and Mg-NbC micron materials prepared using this approach (Supplementary Figs. 3-6). It is worth noting that, to our knowledge, the excellent wetting behaviour seen in the Mg-NbC system has not been reported in any known structural engineering metal/ ex-situ ceramic systems with nano-sized ceramic particles. Ultrahigh tensile strength in Mg-NbC materials The measured tensile strength of Mg-NbC materials (Fig. 2 a ) prepared by solidification of Mg(l)-Mg@NbC colloid is over one order of magnitude higher than pure Mg. For Mg-NbC nano and Mg-NbC submicron materials, the measured strengths are 527 MPa (~10 times higher) and 678 MPa (~14 times higher), respectively. As expected, the strengthening effectiveness in yield strength enhancement for nanoparticles is 33 MPa/vol%, which is significantly higher than that of submicron particles (12 MPa/vol%) and micron particles (8 MPa/vol%) (Supplementary Note Fig. 2 c ). Even with such high load of ceramic particles, the tested Mg-NbC samples exhibited a ductile fracture morphology (Supplementary Fig. 7). The indentation test results (Fig. 2 b ) show an exceptionally high hardness for Mg-NbC submicron (2.59 GPa), exceeding that of 316L stainless steel (2.45 GPa), thought to be due to presence of hard NbC dispersions in the metal matrix. Superior specific elastic modulus and hardness for all Mg-NbC samples over other engineering alloys are also achieved (Supplementary Fig. 8). The mechanical properties of a range of high-performance metallic materials reported in the literature are tabulated in Supplementary Table 1. The product of specific ultimate tensile strength and elongation (which is an indicator for specific toughness) is plotted against the specific elastic modulus in Fig. 2 c . Mg-NbC nano exhibits a unique combination of specific elastic modulus (32 MN·m·kg -1 ) and specific toughness indicator (976 kN·m·%·kg -1 ). This demonstrates the advantages of this ex-situ particle strengthening strategy for simultaneous enhancement of specific stiffness and toughness. Mg/NbC interfaces at atomic scale To understand the wetting behaviour of NbC by molten Mg, as well as the origin of the uniform nanoparticle dispersion and exceptional mechanical performance observed in the Mg-NbC nanocolloid, we now turn to a detailed investigation of the Mg/NbC interface. First, we present atomic-scale experimental evidence using scanning transmission electron microscopy (STEM) combined with electron energy loss spectroscopy (EELS), which reveals the presence of a thin, ordered layer of Mg atoms on the surface of the NbC particles. Next, we support and extend these observations through first-principles density functional theory (DFT) simulations, which provide insight into the atomic bonding and interfacial energetics responsible for this unique surface structure. As the introduction of nanoparticles into molten metal is the most challenging, and their strengthening effectiveness is superior among the three Mg-NbC materials synthesised and studied here, the Mg-NbC nano material has been selected for in-depth interfacial analysis. We employed dedicated STEM imaging combined with EELS core-loss mapping to simultaneously resolve the Mg/NbC {001} interfacial structure and its chemical composition. The images in Fig. 3 a , b provide complementary contrast sensitive to the interfacial atomic structure 43, 44 , while the corresponding compositional distribution is further resolved by EELS elemental mapping in Fig. 3 c . We can readily recognise interfacial atomic layers of different characteristics to the NbC substrate, which are confirmed to be rich in Mg. Predominant atomic features in each layer can be distinguished by the relative compositions across the interface (Fig. 3 c , d ). Notably, this interfacial multilayer complexion is epitaxially coherent with the NbC {001} plane and each Mg atomic column in the terminating Mg layer is seen to coordinate with a C atomic column immediately beneath it. This interfacial Mg atomic arrangement is referred to as C NbC -like arrangement. As the distance away from the NbC {001} surface increases, the Mg atoms arrangement deviates from the C NbC -like configuration and adopts a hexagonal close packed (HCP) structure (Supplementary Fig. 9). First-principles DFT simulation results for the liquid Mg (Mg(l)) and NbC solid substrate system are shown in Fig.4. A snapshot of the atomic arrangements of the Mg(l)/NbC {001} interface (viewed along the NbC direction) equilibrated at 1000K is presented in Fig. 4 a . The corresponding atomic arrangement along the NbC direction is provided for completeness in Supplementary Fig. 10. Strikingly, the simulated interfacial structure shows feature similar to those observed in the post-mortem Mg-NbCnano material after solidification (Fig. 3). The Nb and C atoms in the substrate are well-ordered and the substrate remains solid at 1000K. The Mg atoms in the melt adjacent to the substrate (terminating Mg atoms) exhibit a layering phenomenon with a high degree of solid-like atomic ordering 45 as shown in the atomic density profile (Supplementary Fig. 11). This ordering is quantified using the in-plane ordering coefficient, which is calculated as the average of local order parameters of the atoms within the individual layer at the interface 46 . Our calculations show that the Mg coating layer has an average in-plane ordering coefficient of 0.45, approximately half the value observed for the adjacent solid NbC layer. Each surface C atom is coordinated with one terminating Mg atom. Those terminating Mg atoms exhibit ordered structures similar to that of C atoms in face centred cubic NbC (C NbC -like arrangement). The C-Mg interatomic distances vary with typical lengths between 2.0Å to 2.4Å (Supplementary Fig. 12). The in-plane ordering coefficient rapidly decreases with increasing distance from the NbC substrate to the Mg atomic layers considered. The Mg atoms within the second layer have weak long-range ordering; this region is more liquid-like and correspondingly the in-plane ordering coefficient is just 0.04 (Fig. 4 b ). The calculated net charge distribution at the Mg(l)/NbC {001} interface is shown in Fig. 4 c . The C atoms at the NbC surface layer exhibit the same valence as in the bulk (-1.56e - /C). Meanwhile, surface Nb atoms lose 1.37e - /Nb on an average, which is slightly less than that in the bulk (1.56e - /Nb). The Mg terminal atoms lose 0.2e - /Mg on average, which indicates a moderate charge transfer to the coordinating C atoms beneath. The iso-surfaces of electron density distribution at the Mg(l)/NbC {001} interfacial area in Fig. 4 d show a high electron density (blue shade) within the NbC substrate. The Mg atoms that are bonded to C have low electron density around them, suggesting an ionic nature 47 of the bonds which promoted the localised C NbC -like arrangement of Mg atoms adjacent to the NbC substrate. In contrast, the Mg atoms away from the interface consists of a free-electron cloud and ‘naked’ Mg ions. Overall, the DFT calculations confirm the formation of an ordered layer of Mg atoms being strongly bonded to the surface-terminating C atoms, forming a novel Mg-coated NbC surface (Mg@NbC). The combined experimental observation using atomic-resolution STEM-EELS in the as-solidified Mg-NbC nano sample (Fig.3) with supporting DFT calculations (Fig. 4) unravel a C NbC -like arrangement of the ordered Mg layer on the NbC substrate. This suggests that Mg atoms spontaneously adhere to the surface of the NbC phase, as shown in Supplementary Figure 12, driven by chemical attraction between NbC and Mg(l). Such interfacial adherence results in excellent macroscopic wetting. During solidification, the C NbC -like arrangement of the terminal Mg layer remains stable due to chemical bonding between Mg and C atoms on NbC particles. A typical hcp structure of Mg forms beyond this ordered Mg multilayer, as observed in the solidified sample (Supplementary Fig. 9). NbC particle engulfment by the Mg solidification front In typical solidification processes, ceramic particles (especially at the submicron or nanoscale) are often rejected at the solid/liquid interface due to interfacial energy considerations. This leads to particle segregation and clustering along grain boundaries, which can severely degrade the mechanical performance of the solidified metal. In contrast, as shown in Supplementary Figs. 2 b , 4 c , 6 c , the Mg-NbC system surprisingly exhibited uniform particle dispersions with a wide range of particle sizes (from nanoscale to microscale) in the entire solidified Mg matrix, indicating a favourable interfacial interaction. This characteristic is critical for maintaining the uniform dispersion of nanoparticles initially achieved in the nanocolloidal solution and is a key factor in achieving the observed ultrahigh mechanical performance. Kaptay 48 has proposed an interfacial criterion for spontaneous and forced engulfment of ceramic particles by an advancing solid/liquid interface. The sign of the interfacial force acting between a ceramic particle (c) and a solidification front (s) through the thin layer of a liquid (l) is determined by the sign of the quantity ( Δσ cls = σ cv - σ lv ´ (0.08 + 1.22 ´ cosΘ clv ) where σ cv is the surface energy of the ceramic, σ lv is the surface tension of molten metal and Θ clv is the contact angle of the molten metal on the ceramic substrate). The interfacial force is attractive, i.e., spontaneous engulfment of reinforcing particles by the solidification front is expected, if . Kaptay 48 applied this criterion to a range of Al-ceramic systems (TiC, SiC, Al 2 O 3 , SiO 2 and TiB 2 ) and found that the Δσ cls values are positive for systems in which ceramic particles were observed to be pushed by the solidification front leading to particle segregation at the inter-grain area, which is undesirable for strength enhancement. Due to the formation of an ordered C NbC -like Mg layer on the exposed surfaces of NbC particles, the effective interface between the liquid Mg and particle (Mg(l)/NbC) becomes Mg(l)/Mg terminal at Mg@NbC. This implies perfect wetting of the NbC substrate by the molten Mg with a contact angle approaching zero (Θ clv =0). As a result, during solidification, the advancing Mg front interacts with the Mg@NbC particle to form a Mg(s)/Mg terminal interface rather than a direct Mg(s)/NbC interface. As shown in Fig. 3 a and Supplementary Fig. 12 c , each terminal Mg atom exhibits 12 neighbours (four Mg atoms within the same plane, three Mg atoms in the 1 st Mg layer, four Nb atoms and one C in the underlying NbC layer). Although crystallographically distinct, this face-centred-cubic-like coordination provides each Mg atom in the terminal layer with a coordination number equivalent to that of bulk Mg. Given this structural similarity, the surface energy of the Mg-coated NbC particle can be reasonably approximated as that of pure Mg. This leads to Δσ cls < 0, indicating spontaneous engulfment of NbC particles by the front during solidification of Mg(l)-Mg@NbC colloidal solution 48 . Furthermore, during solidification, Mg atoms at the advancing solidification front form Mg-Mg metallic bonds with the terminal Mg atoms on the surface of NbC particles, allowing the front to propagate through the Mg-coated NbC particles (Supplementary Fig.11). This behaviour indicates a weak correlation between the orientation of NbC particles and the solidification front, resulting in the engulfment of randomly oriented particles. Experimentally, no apparent orientation relationships between the NbC particles and the Mg matrix were observed (Supplementary Figs. 2, 4, 6). It is also notable that NbC possess a significantly higher shear modulus (~230 GPa 49 ) than in-situ formed precipitates 50-53 . These engulfed, chemically bonded high modulus NbC particles within the Mg matrix directly contribute to the effective strengthening 54 of the Mg matrix. Conclusions In conclusion, the combined atomistic-level experimental and theoretical study reveals the formation of an ordered Mg layer bonded to NbC particles (Mg@NbC), which is responsible for the observed spontaneous wetting and engulfment. The resulting material exhibits exceptional specific tensile strength and stiffness, surpassing many high-performance metals. To identify other metal-ceramic systems where the base molten metal spontaneously wets the ceramic nanoparticles, future design should specifically employ ab initio interface structure prediction and interfacial energy calculations. Beyond magnesium, these insights provide a blueprint for designing next-generation structural and functional metal-ceramic systems and scalable nanocolloid-based processing. Declarations Author contributions X.Y. and H.B.N conceptualised the project. They designed the experiments, prepared the materials, carried out the experimental work, processed the data, and performed the analysis. C.F. conducted the DFT calculations. S.N., M.K., T.T., and M.D. prepared the nanosized NbC powder feedstock. T.M. performed the micro-tensile testing. S.W. and Q.M.R. carried out the AC STEM/EELS investigations and data interpretation. F.T. and G.D.W. performed STEM/EDS and 4D-STEM analysis. All authors extensively discussed the data. X.Y., H.B.N., C.F., and S.W. wrote the manuscript, and all authors contributed to editing it. Acknowledgements X.Y. and H.B.N. acknowledge funding from the Engineering and Physical Sciences Research Council (EPSRC), grant number EP/W005042/1. The SuperSTEM Laboratory is the UK National Research Facility for Advanced Electron Microscopy, supported by EPSRC under grant number EP/W021080/1. M.K. acknowledges the fundings of the A-Step program grant number JPMJTR23R9 and of the KSAC program grant number 2024_21 from Japan Science and Technology Agency (JST). S.N. and M.K. also thank to the funding of Bilateral Joint Research, grant number JPJSBP120235704 from the Japan Society for the Promotion of Science (JSPS). X.Y. and H.B.N. thank CBMM (Companhia Brasileira de Metalurgia e Mineração) for supporting a range of NbC powder feedstock. We thank Dr Qing Cai for assistance in microscopy characterisation. References Kwiatkowski da Silva, A. et al . A sustainable ultra-high strength Fe18Mn3Ti maraging steel through controlled solute segregation and α-Mn nanoprecipitation. Nature Communications 13 , 2330 (2022). Nie, J. Precipitation and Hardening in Magnesium Alloys. Metallurgical and Materials Transactions A 43 , 3891–3939 (2012). Shao, X. H., Yang, Z. Q. & Ma, X. L. Strengthening and toughening mechanisms in Mg–Zn–Y alloy with a long period stacking ordered structure. 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Gladman, T. Precipitation hardening in metals. Materials Science and Technology 15 , 30–36 (1999). Methods Fabrication of Mg-NbC materials. NbC powder feedstock with three particulate sizes were used in this study, and their morphology and size distribution are given in Supplementary Fig. 13. The NbC particles with the average size ( D 50 ) of 906 nm were supplied from Companhia Brasileira de Metalurgia e Mineração (CBMM) coded as NbC micron . The NbC particles with the average size ( D 50 ) of 287 nm were acquired from American Elements coded as NbC submicron . The NbC particles with the average size ( D 50 ) of 15 nm were produced using plasma spray chemical synthesis 55-57 coded as NbC nano (Supplementary Figs. 14, 15). To produce NbC nano , a thermal plasma jet was first generated with a hybrid plasma spray system using Ar and H 2 gases. Raw Nb metal powders with an average diameter of 45 µm (Kojundo Chemical Co. Ltd., Japan) were then introduced into the plasma to form high temperature Nb vapour through complete vaporisation. CH 4 gas was also added to the plasma for carburisation of the Nb vapour to form NbC particles. The feed rate of the raw powders and the CH 4 gas flow rate were adjusted to control the NbC nanoparticle size and Nb/C ratio of the NbC solid solution. For particle size distribution measurements, using ImageJ 1.53k software 58 , 1500 particles were analysed for each batch. The NbC nano and NbC submicron powder feedstocks were cold pressed into 16 mm diameter pellets using a Specac Atlas 15T manual hydraulic press with 0.5 ton pressure. In the case of the NbC micron powder, 32 mm diameter pellets were produced by applying 1 ton pressure. The pressed NbC pellets were baked at 110°C for 12h and placed into a steel crucible containing molten Mg (99.95% purity) at 680°C with a protective gas mixture of nitrogen and R134a gas in the ratio of 12:1 (nitrogen flow at 3 L/min, R134a at 0.25 L/min), under ambient pressure, to achieve pressure-less infiltration. During infiltration, the entrapped air in the NbC precursor pellet escapes in the form of bubbles to the molten metal surface. The infiltrated pellets were then solidified at 0.3 K/s cooling rate in protective gas. A pure Mg reference sample was also solidified at the same cooling rate. The volume fraction of the NbC particles in the Mg-NbC materials was calculated based on the measured weight difference between the cold pressed NbC pellet and as-solidified Mg-NbC materials, as well as the density of the pure Mg (1.78 g/cm 3 ) and the NbC phase (7.8 g/cm 3 ). The volume fraction of the NbC phase in as-solidified Mg-NbC nano , Mg-NbC submicron , and Mg-NbC micron samples were 12.2 vol%, 38.7 vol%, and 53.8 vol%, respectively. A summary of the materials information is provided in Supplementary Table 2. Mechanical characterisation. The micro-tensile specimens from as-solidified Mg-NbC nano and Mg-NbC submicron materials were prepared using a Thermo Fisher Scientific Scios 2 DualBeam focused ion beam-scanning electron microscope (FIB-SEM) and tested using a FemtoTools FT-NMT04 IN-SITU Nanoindentor under Field Emission-SEM (FE-SEM) observation by Scios 2 (Supplementary Fig. 16). The specimens were sectioned, lifted-out from the as-solidified Mg-NbC samples and then attached to a tungsten needle by Pt deposition into a prefabricated hole whose size conforms to the shape of the lifted sample. This was the fixed side in the tensile testing rig. The specimen was shaped into a dog-bone geometry with rectangular cross section (~10 mm gauge length and 12 mm 2 cross sectional area). The dog-bone specimen was attached to a Si gripper that connected to a microforce sensing probe (FT-S200’000) within FT-NNMT04. The micro-tensile test was performed in the displacement control mode and a strain rate of 1´10 -4 s -1 . The video recording of the in-situ tensile tests is presented in supplementary files (Supplementary Videos 1-3). The macro-tensile tests of the as-solidified Mg-13vol%NbC micron material and reference pure Mg were conducted on a Instron 5500 Universal Electromechanical Testing System with a constant cross head speed of 0.225 mm/min (2×10 −4 s −1 initial strain rate) and the results are shown in Supplementary Note Fig. 2 c . A Micro Materials NanoTest ALPHA with a Berkovich tip was used for nanoindentation tests with load-control to a maximum load of 100 mN with a 6.7 mN/s loading rate, held for 10 s, and unloaded at 6.7 mN/s. Hardness and elastic modulus are evaluated from the load-indentation depth curves. Microstructure observations. A Zeiss Crossbeam 340 SEM and Thermo Fisher Scientific Talos F200X were used to investigate the microstructure of the NbC powder feedstock and the Mg-NbC samples. Scanning transmission electron microscopy (STEM) images and energy dispersive x-ray spectroscopy (EDS) elemental maps were collected using the Talos F200X instrument. Atomic-resolution STEM imaging and electron energy loss spectroscopy (EELS) mapping were conducted using an aberration corrected Nion UltraSTEM100 working at 100 kV. The microscope is equipped with a cold-FEG emitter with 0.3 eV native energy spread. With a fifth-order probe aberration corrector, the microscope optics can be configured to enable a probe size of < 1 Å at 100 kV with a convergence semi-angle of 30 mrad and a probe current of 30 pA in the conditions used for these experiments. The semi-angular ranges for high-angle annular-dark-field (HAADF), medium-angle annular-dark-field (MAADF) images and annular-bright-field (ABF) images were 89 -195 mrad, 52-89 mrad (or 30-65 mrad when acquired simultaneously with ABF images), and 10-30 mrad, respectively. Electron energy loss spectra were acquired on a Gatan Enfina spectrometer that is retrofitted with a Quantum Detectors Merlin EELS hybrid pixel camera. EELS spectrum images (SIs) were acquired in “event-streamed” mode using a 36 mrad collection semi-angle. Leveraging the instrument’s exceptional stability, characterised by a minor sample drift under experimental conditions, multiple consecutive scans with short pixel dwell times (3 or 5 ms/pixel) were accumulated. This approach enabled sufficient signal acquisition while minimizing noise and sample damage through repeated acquisitions. Prior to data processing, the EELS SI dataset was denoised via the built-in principal component analysis (PCA) function in Gatan Microscopy Suite 3.6 (GMS 3.6), with careful inspection of residuals to ensure artifact-free reconstruction. Notably, the near-ideal Poisson noise characteristics of data collected using next generation hybrid pixel detectors make them particularly well-suited for PCA-based denoising, enabling enhanced signal extraction with minimal artifact introduction 59 . EELS elemental maps were generated in two ways. For SIs containing the Nb M edges (205 eV) and C K (284 eV) in close proximity, we used model-based EELS quantification function in GMS 3.6 to separate the two signal components for elemental mapping. This method was applied to create Fig. 1 b , Supplementary Fig. 14 d and Fig. 15 d , and the C K map in Fig. 3 c . For the Mg K (1305 eV, in Fig. 3 c ) and Nb L 2,3 (2465 eV, in Fig. 3c, Supplementary Fig. 14 e and Fig. 15 e ) edges, we first subtracted a decaying background preceding each edge using a fitted power-law function and then integrated the EELS edge intensity over a 50 eV window from each edge onset. EELS map intensities are shown using a false colour scale, where low intensity indicates lower relative elemental concentration, and higher contrast reflects a relative increase in concentration. We note that two consecutive SIs were acquired in the same region in Fig. 3 c to cover a wide energy range involving all the aforementioned core-loss edges, while only C K , Nb L 2,3 and Mg K were selected for illustration in the main text. Cross-sections of the bulk samples were prepared using standard metallographic methods with the oil-based diamond suspensions. TEM specimens from the Mg-NbC samples were initially sliced from the bulk and ground to a thickness of ~100 µm, followed by dimpling using a Gatan dimple grinder system and subsequent thinning using ion milling with a Gatan PIPS 695 instrument that operated at 3-5 kV and beam angles of 3-5°. To remove damaged layers and any amorphous structure on the TEM foil surface, a final polishing step was performed at 1 kV with Ar⁺ ions at a 7° incident beam angle. Electron backscattered diffraction (EBSD) was performed to characterise the grain size of Mg in Mg-NbC samples. Specimens were placed in the Tescan Magna UHR-SEM tilted 70° from the horizontal plane towards the EBSD camera with a 30 kV electron beam, 13 nm spot size and 80-100 nm step size. The 4D-STEM based orientation/phase mapping was applied to produce crystallographic maps of the Mg-NbC nano specimen at high resolution using a Talos F200X and NanoMegas ASTAR system at 200 kV, 2 nm step size. The data analysis was conducted by ATEX 5.0 software (Academic Edition) 60 . The X-ray diffraction (XRD) spectrum for Mg-13vol%NbC micron sample was acquired using a Bruker D8 ADVANCE XRD diffractometer with a Cu K a (l= 0.1542 nm) radiation source, and the results are shown in Supplementary Note Fig. 2 b . The candidate phases for matching are selected from Powder Diffraction File™ (PDF ® ) database. DFT calculations . The present ab initio molecular dynamics (AIMD) study employs the first-principles code VASP (Vienna Ab initio Simulation Package) 61 that utilizes the periodic boundary conditions (PBC). Supercells were built for modelling the interfaces between liquid Mg and NbC substrates. NbC {001} substrate has an equal number of Nb and C atoms at the surface, being electronically neutral and non-polar. The number of liquid Mg atoms for the systems is fixed to be 300, while the number of Nb atoms and C atoms are fixed to be 72. A tetragonal supercell was created with a = 3 a 0 for the Mg(l)/NbC {001} interface, where a 0 is the length of the axis of the conventional NbC cell with consideration of the thermal expansion at the simulation temperature 62 . The length of the c -axis is determined by the thickness of the NbC slab and the volume of the Mg atoms with the density at the simulation temperature 62 . The built supercells are summarized in Supplementary Table 3 and the related configurations are shown in Supplementary Fig. 17 a . To avoid artificial interface interactions, a space of about 2.0 Å was made between the substrate atoms and the liquid Mg atoms. VASP employs the electronic density-functional theory (DFT) within the projector-augmented wave framework 63 . The generalised gradient approximation (GGA-PBE) was used for the exchange and correlation terms 64 . The cut-off energy for the ab initio molecular dynamics simulations is 320.0 eV and Г-point in the Brillouin zone is used as there is a lack of symmetry in the liquid/solid interfaces 61, 65 . The simulation temperature is set to be 1000 K. A two-step approach was used: first AIMD simulations were performed with the substrate atoms fixed for about 300 steps (1.5 femtosecond (fs) per step). Then, the AIMD simulations are continued with relaxation of all the atoms. The simulations revealed thermal equilibration after about 1 picosecond (ps) (see Supplementary Fig. 17). This approach avoids risks of collective movements of atoms during the AIMD simulations 45 . Methods References Kambara, M. et al . Nano-composite Si particle formation by plasma spraying for negative electrode of Li ion batteries. J. Appl. Phys. 115 , 143302 (2014). Kambara, M., Huang, H. & Yoshida, T. in Advanced Plasma Technology 401–419 (Wiley-VCH, ed., 2008). Yoshida, T. Toward a new era of plasma spray processing. Pure Appl. Chem. 78 , 1093–1107 (2006). Schneider, C. A., Rasband, W. S. & Eliceiri, K. W. NIH Image to ImageJ: 25 years of image analysis. Nature Methods 9 , 671–675 (2012). Haberfehlner, G. et al . Benefits of direct electron detection and PCA for EELS investigation of organic photovoltaics materials. Micron 140 , 102981 (2021). Beausir B. & Eundenberger J.-J. Analysis Tools for Electron and X-ray diffraction, ATEX-software. (2017). Kresse, G. & Hafner, J. Ab initio molecular-dynamics simulation of the liquid-metal--amorphous-semiconductor transition in germanium. Phys. Rev. B 49 , 14251–14269 (1994). Tirumalasetty, G. K. et al . Characterization of NbC and (Nb,Ti)N nanoprecipitates in TRIP assisted multiphase steels. Acta Materialia 59 , 7406–7415 (2011). Blöchl, P. E. Projector augmented-wave method. Phys. Rev. B 50 , 17953–17979 (1994). Perdew, J. P., Burke, K. & Ernzerhof, M. Generalized Gradient Approximation Made Simple. Phys. Rev. Lett. 77 , 3865–3868 (1996). Monkhorst, H. J. & Pack, J. D. Special points for Brillouin-zone integrations. Phys. Rev. B 13 , 5188–5192 (1976). Additional Declarations There is NO Competing Interest. Supplementary Files SupplementaryInformation.pdf Supplementary Information supplementaryvideosubmicron1.mp4 S. Video_submicron supplementaryvideonano1.mp4 S. Video_nano supplementaryvideopureMg1.mp4 S. Video_Mg Cite Share Download PDF Status: Under Review Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7589727","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":530228227,"identity":"62cce048-79ef-4b71-8fe1-04ca659da03f","order_by":0,"name":"Hari Babu 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12:48:51","extension":"html","order_by":25,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":117974,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-7589727/v1/2037b037b85c3c427f01fab5.html"},{"id":93778819,"identity":"b3689fd9-d8d5-45f0-baa8-b18843a45b2e","added_by":"auto","created_at":"2025-10-17 12:48:50","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":372396,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003ePreparation of Mg-NbC sample by nanocolloid solidification. a, \u003c/strong\u003eSchematic diagram of the material preparation (molten Mg infiltration into packed NbC powders and solidification of Mg(l)-Mg@NbC nanocolloid).\u003cstrong\u003e \u003c/strong\u003eThe bright-field TEM image shown on the right side of \u003cstrong\u003ea\u003c/strong\u003e, reveals a uniform dispersion of nanoparticles in the solidified Mg-NbC\u003csub\u003enano\u003c/sub\u003e.\u003cstrong\u003e b, \u003c/strong\u003eHigh-angle annular dark-field (HAADF) STEM image and the corresponding simultaneously acquired EELS maps for Nb, C, Mg and false-colour composite, confirming the presence of the Mg phase in between NbC nanoparticles.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-7589727/v1/2e33fd3e9771d5ddb58491e6.png"},{"id":93777317,"identity":"306a3613-d81d-4a83-9f00-efd1992c3c5c","added_by":"auto","created_at":"2025-10-17 12:40:50","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":324167,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eMechanical properties of as-solidified Mg-NbC materials.\u003c/strong\u003e \u003cstrong\u003ea,\u003c/strong\u003e Tensile stress-strain curves of as-solidified Mg-NbC\u003csub\u003esubmicron\u003c/sub\u003e, Mg-NbC\u003csub\u003enano\u003c/sub\u003e and Mg. The improvement in yield stress is marked and the insets are the images of the corresponding micro-tensile samples. Scale bars, 5 μm. \u003cstrong\u003eb,\u003c/strong\u003e The indentation load-depth curves of Mg-NbC with benchmark engineering alloys (AZ91D alloy (Mg), AlMgSc Scalmalloy\u003csup\u003e®\u003c/sup\u003e (Al), and 316L stainless steel). The Mg-NbC\u003csub\u003esubmicron\u003c/sub\u003e shows a higher indent resistance than the engineering Mg, Al and Steel alloys. \u003cstrong\u003ec,\u003c/strong\u003e The product of specific ultimate tensile strength and elongation against the specific elastic modulus of as-solidified Mg-NbC\u003csub\u003enano \u003c/sub\u003estands out, in comparison with the values for other high performance metallic materials reported in the literature (Magnesium alloy\u003csup\u003e6, 17-21\u003c/sup\u003e, Aluminium alloy\u003csup\u003e9, 22-24\u003c/sup\u003e, Titanium alloy\u003csup\u003e25-28\u003c/sup\u003e, and Advanced High Strength Steel (AHSS)\u003csup\u003e1, 29-42\u003c/sup\u003e.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-7589727/v1/19b4b242f13ad8673835a587.png"},{"id":93777320,"identity":"1d970e48-4a06-4fd2-a003-4bb61faa418a","added_by":"auto","created_at":"2025-10-17 12:40:50","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":388086,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eAtomic resolution characterisation of structure and composition across the Mg/NbC\u003c/strong\u003e\u003csub\u003e\u003cstrong\u003e{001}\u003c/strong\u003e\u003c/sub\u003e\u003cstrong\u003e interface by STEM imaging and EELS mapping.\u003c/strong\u003e \u003cstrong\u003ea, \u003c/strong\u003eHAADF and \u003cstrong\u003eb, \u003c/strong\u003eannular bright-field (ABF) images of the interface. \u003cstrong\u003ec\u003c/strong\u003e, HAADF survey image and the simultaneously acquired EELS maps for C, Nb, Mg and a composite elemental superposition, and \u003cstrong\u003ed,\u003c/strong\u003e Compositional and HAADF-contrast line profiles plotted along the white arrow in \u003cstrong\u003ec\u003c/strong\u003e, with intensity values averaged over the arrow’s width. (dashed lines indicate NbC\u003csub\u003esurface\u003c/sub\u003e and Mg\u003csub\u003eterminal\u003c/sub\u003e, as a guide to the eye). For all the STEM images and EELS maps, the incident beam is parallel to the zone axis \u0026lt;110\u0026gt;\u003csub\u003eNbC\u003c/sub\u003e. Schematic atomic configurations are overlaid on the images in \u003cstrong\u003ea\u003c/strong\u003e and \u003cstrong\u003eb\u003c/strong\u003e,\u003cstrong\u003e \u003c/strong\u003ein which green, dark brown and orange spheres represent Nb, C and Mg atoms, respectively. The compositional line profiles across the interface (averaged over the width of the arrow overlaid on the composite colour map) confirms the formation of an ordered Mg multilayer on the NbC surface.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-7589727/v1/e171d4487aec8d3a5edb7a39.png"},{"id":93780047,"identity":"2dc4e916-4bf1-4b35-b1e7-ffdd9b8ed6c6","added_by":"auto","created_at":"2025-10-17 12:56:51","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":345122,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eDFT analysis of the Mg(l)-NbC. a,\u003c/strong\u003e A snapshot of the atomic arrangements of Mg(l)/NbC\u003csub\u003e{001} \u003c/sub\u003einterface equilibrated at 1000K. Green, brown and orange spheres represent Nb, C and Mg atoms, respectively. Dashed lines indicate individual atomic layers. \u003cstrong\u003eb,\u003c/strong\u003e In-plane ordering coefficient at the interfaces for configurations summed over 3 ps. Insets are the atomic arrangement of the Nb and C atoms at the outmost substrate layer, Mg atoms at the terminal layer (Mg\u003csub\u003eterminal\u003c/sub\u003e), Mg atoms at 1\u003csup\u003est\u003c/sup\u003e layer (Mg\u003csub\u003e1st\u003c/sub\u003e) and 2\u003csup\u003end\u003c/sup\u003e layer (Mg\u003csub\u003e2nd\u003c/sub\u003e), Strong ordering is seen within the Mg\u003csub\u003eterminal\u003c/sub\u003e atomic layer. Then the ordering coefficient rapidly reduces for Mg\u003csub\u003e2nd\u003c/sub\u003e atomic layer which is typical for liquid-like structures. \u003cstrong\u003ec,\u003c/strong\u003e The Bader charges at atomic sites at the Mg(l)/NbC\u003csub\u003e{001}\u003c/sub\u003e interface in which the black, blue and green data points represent net charges at C, Mg and Nb sites, respectively. Dashed green and orange vertical lines represent the NbC\u003csub\u003esurface\u003c/sub\u003e atomic layer and Mg\u003csub\u003etenminal\u003c/sub\u003e atomic layer, respectively. Dotted black and green horizontal lines represent charge values at C and Nb, respectively, in bulk NbC. \u003cstrong\u003ed,\u003c/strong\u003e Iso-surfaces of electron density distribution (ρ\u003csub\u003e0\u003c/sub\u003e(\u003cem\u003e\u003cstrong\u003er\u003c/strong\u003e\u003c/em\u003e) = 0.018e/Å\u003csup\u003e3\u003c/sup\u003e). The yellow clouds represent the iso-surfaces with ρ\u003csub\u003e0\u003c/sub\u003e(\u003cem\u003e\u003cstrong\u003er\u003c/strong\u003e\u003c/em\u003e) = 0.018e/Å\u003csup\u003e3\u003c/sup\u003e. Blue and white coloured region represents higher and lower electron density, respectively. The red spheric clouds in the substrate originate from the Nb 4d electrons.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-7589727/v1/f119374bb5b33a8b977c6e5a.png"},{"id":93961262,"identity":"0f21e343-f7c4-4f70-bb9e-59fdee4076d6","added_by":"auto","created_at":"2025-10-20 17:11:14","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2442073,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7589727/v1/790b4e61-69a5-4422-9b7a-c36e6d11caa5.pdf"},{"id":93777323,"identity":"b44ab4d9-0895-4d09-bbf1-96cda8111b11","added_by":"auto","created_at":"2025-10-17 12:40:51","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":2609850,"visible":true,"origin":"","legend":"Supplementary Information","description":"","filename":"SupplementaryInformation.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7589727/v1/14a757a40fe6ca2188fe2e09.pdf"},{"id":93777334,"identity":"9a0ddf45-f412-45bb-9f09-7342898c10eb","added_by":"auto","created_at":"2025-10-17 12:40:51","extension":"mp4","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":26313271,"visible":true,"origin":"","legend":"S. Video_submicron","description":"","filename":"supplementaryvideosubmicron1.mp4","url":"https://assets-eu.researchsquare.com/files/rs-7589727/v1/f7a8f7041e234034476270f5.mp4"},{"id":93777355,"identity":"e11e57af-6260-49ac-8ca7-b268bc44730b","added_by":"auto","created_at":"2025-10-17 12:40:52","extension":"mp4","order_by":3,"title":"","display":"","copyAsset":false,"role":"supplement","size":37208466,"visible":true,"origin":"","legend":"S. Video_nano","description":"","filename":"supplementaryvideonano1.mp4","url":"https://assets-eu.researchsquare.com/files/rs-7589727/v1/b6cc12c3517a9d78d5170429.mp4"},{"id":93777352,"identity":"babcee61-782f-433f-a8a1-cef59e49a8bd","added_by":"auto","created_at":"2025-10-17 12:40:52","extension":"mp4","order_by":4,"title":"","display":"","copyAsset":false,"role":"supplement","size":58350113,"visible":true,"origin":"","legend":"S. Video_Mg","description":"","filename":"supplementaryvideopureMg1.mp4","url":"https://assets-eu.researchsquare.com/files/rs-7589727/v1/5cc37865ca16cdd23451b9f6.mp4"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e Competing Interest.","formattedTitle":"Ultrahigh strength magnesium via solidification of nanocolloid","fulltext":[{"header":"Full Text","content":"\u003cp\u003eMg has a low density of 1.78 g\u0026middot;cm\u003csup\u003e-3\u003c/sup\u003e and a high damping capacity with a loss factor ~11.8\u0026times;10\u003csup\u003e-3\u003c/sup\u003e (~10 times higher than Al and Steel), and thus offers tremendous potential in achieving lightweight vehicles with improved fuel economy and reduced CO\u003csub\u003e2\u003c/sub\u003e emission. However, the yield strengths of the most used automotive Mg alloys are in the range of 100-200 MPa, which is just nearly half that of Al alloys and 1/4 that of high strength steels; thus, the industry is not fully able to utilise their lightweight potential.\u003c/p\u003e\n\u003cp\u003eAmong the major alloy strengthening mechanisms, the uniform dispersion of nanoscale secondary phase precipitates is particularly effective\u003csup\u003e1\u003c/sup\u003e. Alloying additions of rare earth (RE) elements in Mg alloys results in a significant strength improvement due to the effective precipitation of RE-containing phases upon heat treatment \u003csup\u003e2, 3\u003c/sup\u003e. Despite the promise of this approach, the high cost and limited availability of RE elements have historically hindered the widespread use of Mg-RE alloys in industry, with their potential only recently being actively explored\u003csup\u003e4, 5\u003c/sup\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAs another strategy, fine-grained magnesium produced through thermomechanical processing is typically combined with precipitation hardening to achieve high strength\u003csup\u003e6\u003c/sup\u003e. However, the resulting microstructures often exhibit limited thermal stability, which compromises their performance under demanding service conditions.\u003c/p\u003e\n\u003cp\u003eCeramic particles with high shear moduli, as an alternative approach to the \u003cem\u003ein-situ\u003c/em\u003e formed precipitates, can serve as the non-deforming particles that favour the Orowan strengthening mechanism\u003csup\u003e7\u003c/sup\u003e. Their strengthening effect depends mainly on particle size and number density. This approach does not require specially tailored alloy compositions or complex thermomechanical processing routes. Reported data on various metallic systems highlight that in addition to ceramic particles contributing to strengthening\u003csup\u003e8-12\u003c/sup\u003e, the resulting nano-sized grain structure of the metallic matrix significantly improves the overall mechanical strength\u003csup\u003e13, 14\u003c/sup\u003e. For example, in Mg alloys, a multi-step external field treatment on molten metal followed by severe plastic deformation were conducted to disperse SiC nanoparticles\u003csup\u003e13\u003c/sup\u003e. In molybdenum alloys, the \u003cem\u003ein-situ\u003c/em\u003e reaction of the precursor compounds\u003csup\u003e14\u003c/sup\u003e was utilised to introduce the nano-sized ceramic particles and then a rolling process was conducted to disperse the nanoparticles and refine the Mo grain size. These ceramic phases are thermally stable and can effectively retain their strengthening effect at elevated temperatures\u003csup\u003e9, 15\u003c/sup\u003e. This is also the case of Al incorporated with graphene-coated MgO nanoparticles\u003csup\u003e9\u003c/sup\u003e, \u003cem\u003evia\u003c/em\u003e the powder metallurgy route, which showed improved strength and creep resistance at temperatures as high as 500\u0026deg;C. Similarly, non-equilibrium solidification in additive manufacturing was applied to incorporate La\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e nanoparticles in a medium entropy alloy matrix and demonstrated further enhancement of creep property at 1093\u0026deg;C\u003csup\u003e15\u003c/sup\u003e compared with the pure alloy parent phase.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eWe report here an ultrahigh tensile strength of ~680 MPa in Mg produced by solidification of a Mg colloid containing fine scale NbC dispersions. The excellent wetting characteristics of the NbC phase with molten magnesium enabled the processing of such high strength material. We investigate the fundamental mechanism for the atomic interaction between Mg and NbC using aberration-corrected scanning transmission electron microscopy (STEM) and electron energy loss spectroscopy (EELS). We further perform density functional theory (DFT) calculations to investigate the interfacial interactions and atomic arrangements at the liquid Mg/NbC (Mg(l)/NbC) interfaces, with an emphasis on the non-polar NbC {001} surface that terminates most produced NbC nanoparticles. This study reveals that the formation of an ordered layer of Mg atoms, strongly bonded to the carbon atoms on the NbC {001} surface, results in a novel Mg-coated NbC (Mg@NbC) colloid, which plays a critical role in the observed excellent wetting characteristics. During solidification of the Mg(l)-Mg@NbC colloid, the Mg solidification front spontaneously engulfs the NbC dispersoids into the growing Mg grains. In the resulting solidified alloys, these embedded dispersoids can effectively contribute to strengthening, similar to the role of coherent precipitates in monolithic Mg alloys.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMg-NbC material by solidification of colloidal solution\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eHistorically, the preparation of stable high-temperature colloidal solutions \u003cem\u003evia\u003c/em\u003e the combination of molten metal and ceramic particulate dispersions has not been possible, due to the poor wettability of the ceramic particles by the molten metal\u003csup\u003e16\u003c/sup\u003e. We have identified the metal-ceramic (Mg-NbC) system as an excellent candidate to realise this task, thanks to perfect wetting characteristics that enable the production of a high-temperature nanocolloidal solution consisting of NbC nano-dispersions in molten Mg using a simple, practical and scalable method.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eFor producing nanocolloidal solutions, we first compressed NbC powders with particle size of 15 nm (NbC\u003csub\u003enano\u003c/sub\u003e), 287 nm (NbC\u003csub\u003esubmicron\u003c/sub\u003e) and 906 nm (NbC\u003csub\u003emicron\u003c/sub\u003e) (see methods for details) into bulk pellets and then infiltrated molten Mg into these compressed pellets at ambient pressure (Fig. 1). The colloidal solution was then solidified using a conventional casting process to obtain the Mg-NbC material that consists of uniform NbC nanodispersoids in the Mg matrix (Supplementary Figs. 1, 2 for the case of the smaller-sized NbC\u003csub\u003enano\u003c/sub\u003e particles). During infiltration into the compressed powder pellet, molten Mg wetted the nanoparticles causing them to detach from each other and form a stable nanocolloid (see Supplementary Note). This preparation method significantly simplifies the incorporation of \u003cem\u003eex-situ\u003c/em\u003e ceramic nanoparticles into the molten metal with a uniform dispersion. Similarly, uniform dispersions can also be seen in Mg-NbC\u003csub\u003esubmicron\u003c/sub\u003e and Mg-NbC\u003csub\u003emicron\u003c/sub\u003e materials prepared using this approach (Supplementary Figs. 3-6). It is worth noting that, to our knowledge, the excellent wetting behaviour seen in the Mg-NbC system has not been reported in any known structural engineering metal/\u003cem\u003eex-situ\u003c/em\u003e ceramic systems with nano-sized ceramic particles.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eUltrahigh tensile strength in Mg-NbC materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe measured tensile strength of Mg-NbC materials (Fig. 2\u003cstrong\u003ea\u003c/strong\u003e) prepared by solidification of Mg(l)-Mg@NbC colloid is over one order of magnitude higher than pure Mg. For Mg-NbC\u003csub\u003enano\u003c/sub\u003e and Mg-NbC\u003csub\u003esubmicron\u003c/sub\u003e materials, the measured strengths are 527 MPa (~10 times higher) and 678 MPa (~14 times higher), respectively. As expected, the strengthening effectiveness in yield strength enhancement for nanoparticles is 33 MPa/vol%, which is significantly higher than that of submicron particles (12 MPa/vol%) and micron particles (8 MPa/vol%) (Supplementary Note Fig. 2\u003cstrong\u003ec\u003c/strong\u003e). Even\u0026nbsp;with such high load of ceramic particles, the tested Mg-NbC\u003csub\u003e\u0026nbsp;\u003c/sub\u003esamples exhibited a ductile fracture morphology (Supplementary Fig. 7).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe indentation test results (Fig. 2\u003cstrong\u003eb\u003c/strong\u003e) show an exceptionally high hardness for Mg-NbC\u003csub\u003esubmicron\u003c/sub\u003e (2.59 GPa), exceeding that of 316L stainless steel (2.45 GPa), thought to be due to presence of hard NbC dispersions in the metal matrix. Superior specific elastic modulus and hardness for all Mg-NbC samples over other engineering alloys are also achieved (Supplementary Fig. 8).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe mechanical properties of a range of high-performance metallic materials reported in the literature are tabulated in Supplementary Table 1.\u0026nbsp;The\u0026nbsp;product of specific ultimate tensile strength and elongation (which is an indicator for specific toughness) is plotted against the specific elastic modulus in Fig. 2\u003cstrong\u003ec\u003c/strong\u003e. Mg-NbC\u003csub\u003enano\u003c/sub\u003e exhibits a unique combination of specific elastic modulus (32 MN\u0026middot;m\u0026middot;kg\u003csup\u003e-1\u003c/sup\u003e) and specific toughness indicator (976 kN\u0026middot;m\u0026middot;%\u0026middot;kg\u003csup\u003e-1\u003c/sup\u003e). This demonstrates the advantages of this \u003cem\u003eex-situ\u003c/em\u003e particle strengthening strategy for simultaneous enhancement of specific stiffness and toughness.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMg/NbC interfaces at atomic scale\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTo understand the wetting behaviour of NbC by molten Mg, as well as the origin of the uniform nanoparticle dispersion and exceptional mechanical performance observed in the Mg-NbC nanocolloid, we now turn to a detailed investigation of the Mg/NbC interface. First, we present atomic-scale experimental evidence using scanning transmission electron microscopy (STEM) combined with electron energy loss spectroscopy (EELS), which reveals the presence of a thin, ordered layer of Mg atoms on the surface of the NbC particles. Next, we support and extend these observations through first-principles density functional theory (DFT) simulations, which provide insight into the atomic bonding and interfacial energetics responsible for this unique surface structure.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAs the introduction of nanoparticles into molten metal is the most challenging, and their strengthening effectiveness is superior among the three Mg-NbC materials synthesised and studied here, the Mg-NbC\u003csub\u003enano\u003c/sub\u003e material has been selected for in-depth interfacial analysis. We employed dedicated STEM imaging combined with EELS core-loss mapping to simultaneously resolve the Mg/NbC\u003csub\u003e{001}\u003c/sub\u003e interfacial structure and its chemical composition. The images in Fig. 3\u003cstrong\u003ea\u003c/strong\u003e,\u003cstrong\u003eb\u003c/strong\u003e provide complementary contrast sensitive to the interfacial atomic structure\u003csup\u003e43, 44\u003c/sup\u003e, while the corresponding compositional distribution is further resolved by EELS elemental mapping in Fig. 3\u003cstrong\u003ec\u003c/strong\u003e. We can readily recognise interfacial atomic layers of different characteristics to the NbC substrate, which are confirmed to be rich in Mg. Predominant atomic features in each layer can be distinguished by the relative compositions across the interface (Fig. 3\u003cstrong\u003ec\u003c/strong\u003e,\u003cstrong\u003ed\u003c/strong\u003e). Notably, this interfacial multilayer complexion is epitaxially coherent with the NbC {001} plane and each Mg atomic column in the terminating Mg layer is seen to coordinate with a C atomic column immediately beneath it. This interfacial Mg atomic arrangement is referred to as C\u003csub\u003eNbC\u003c/sub\u003e-like arrangement. As the distance away from the NbC {001} surface increases, the Mg atoms arrangement deviates from the C\u003csub\u003eNbC\u003c/sub\u003e-like configuration and adopts a hexagonal close packed (HCP) structure (Supplementary Fig. 9).\u003c/p\u003e\n\u003cp\u003eFirst-principles DFT simulation results for the liquid Mg (Mg(l)) and NbC solid substrate system are shown in Fig.4. A snapshot of the atomic arrangements of the Mg(l)/NbC\u003csub\u003e{001}\u0026nbsp;\u003c/sub\u003einterface (viewed along the \u0026lt;100\u0026gt;\u003csub\u003eNbC\u003c/sub\u003e direction) equilibrated at 1000K is presented in Fig. 4\u003cstrong\u003ea\u003c/strong\u003e. The corresponding atomic arrangement along the \u0026lt;110\u0026gt;\u003csub\u003eNbC\u003c/sub\u003e direction is provided for completeness in Supplementary Fig. 10. Strikingly, the simulated interfacial structure shows feature similar to those observed in the post-mortem Mg-NbCnano material after solidification (Fig. 3). The Nb and C atoms in the substrate are well-ordered and the substrate remains solid at 1000K.\u0026nbsp;The Mg atoms in the melt adjacent to the substrate (terminating Mg atoms) exhibit a layering phenomenon with a high degree of solid-like atomic ordering\u003csup\u003e45\u003c/sup\u003e as shown in the atomic density profile (Supplementary Fig. 11). This ordering is quantified using the in-plane ordering coefficient, which is calculated as the average of local order parameters of the atoms within the individual layer at the interface\u003csup\u003e46\u003c/sup\u003e. Our calculations show that the Mg coating layer has an average in-plane ordering coefficient of 0.45, approximately half the value observed for the adjacent solid NbC layer. Each surface C atom is coordinated with one terminating Mg atom. Those terminating Mg atoms exhibit ordered structures similar to that of C atoms in face centred cubic NbC (C\u003csub\u003eNbC\u003c/sub\u003e-like arrangement). The C-Mg interatomic distances vary with typical lengths between 2.0\u0026Aring; to 2.4\u0026Aring; (Supplementary Fig. 12). The in-plane ordering coefficient rapidly decreases with increasing distance from the NbC substrate to the Mg atomic layers considered. The Mg atoms within the second layer have weak long-range ordering; this region is more liquid-like and correspondingly the in-plane ordering coefficient is just 0.04 (Fig. 4\u003cstrong\u003eb\u003c/strong\u003e).\u003c/p\u003e\n\u003cp\u003eThe calculated net charge distribution at the Mg(l)/NbC\u003csub\u003e{001}\u003c/sub\u003e interface is shown in Fig. 4\u003cstrong\u003ec\u003c/strong\u003e. The C atoms at the NbC surface layer exhibit the same valence as in the bulk (-1.56e\u003csup\u003e-\u003c/sup\u003e/C). Meanwhile, surface Nb atoms lose 1.37e\u003csup\u003e-\u003c/sup\u003e/Nb on an average, which is slightly less than that in the bulk (1.56e\u003csup\u003e-\u003c/sup\u003e/Nb). The Mg\u003csub\u003eterminal\u003c/sub\u003e atoms lose 0.2e\u003csup\u003e-\u003c/sup\u003e/Mg on average, which indicates a moderate charge transfer to the coordinating C atoms beneath. The iso-surfaces of electron density distribution at the Mg(l)/NbC\u003csub\u003e{001}\u003c/sub\u003e interfacial area in Fig. 4\u003cstrong\u003ed\u003c/strong\u003e show a high electron density (blue shade) within the NbC substrate. The Mg atoms that are bonded to C have low electron density around them, suggesting an ionic nature\u003csup\u003e47\u003c/sup\u003e of the bonds which promoted the localised C\u003csub\u003eNbC\u003c/sub\u003e-like arrangement of Mg atoms adjacent to the NbC substrate. In contrast, the Mg atoms away from the interface consists of a free-electron cloud and \u0026lsquo;naked\u0026rsquo; Mg ions.\u003c/p\u003e\n\u003cp\u003eOverall, the DFT calculations confirm the formation of an ordered layer of Mg atoms being strongly bonded to the surface-terminating C atoms, forming a novel Mg-coated NbC surface (Mg@NbC).\u003c/p\u003e\n\u003cp\u003eThe combined experimental observation using atomic-resolution STEM-EELS in the as-solidified Mg-NbC\u003csub\u003enano\u003c/sub\u003e sample (Fig.3) with supporting DFT calculations (Fig. 4) unravel a C\u003csub\u003eNbC\u003c/sub\u003e-like arrangement of the ordered Mg layer on the NbC substrate. This suggests that Mg atoms spontaneously adhere to the surface of the NbC phase, as shown in Supplementary Figure 12, driven by chemical attraction between NbC and Mg(l). Such interfacial adherence results in excellent macroscopic wetting. During solidification, the C\u003csub\u003eNbC\u003c/sub\u003e-like arrangement of the terminal Mg layer remains stable due to chemical bonding between Mg and C atoms on NbC particles. A typical hcp structure of Mg forms beyond this ordered Mg multilayer, as observed in the solidified sample (Supplementary Fig. 9).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eNbC particle engulfment by the Mg solidification front\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn typical solidification processes, ceramic particles\u0026nbsp;(especially at the submicron or nanoscale) are often rejected at the solid/liquid interface due to interfacial energy considerations. This leads to particle segregation and clustering along grain boundaries, which can severely degrade the mechanical performance of the solidified metal. In contrast, as shown in Supplementary Figs. 2\u003cstrong\u003eb\u003c/strong\u003e, 4\u003cstrong\u003ec\u003c/strong\u003e, 6\u003cstrong\u003ec\u003c/strong\u003e, the Mg-NbC system surprisingly exhibited uniform particle dispersions with a wide range of particle sizes (from nanoscale to microscale) in the entire solidified Mg matrix, indicating a favourable interfacial interaction. This characteristic is critical for maintaining the uniform dispersion of nanoparticles initially achieved in the nanocolloidal solution and is a key factor in achieving the observed ultrahigh mechanical performance. Kaptay\u003csup\u003e48\u003c/sup\u003e has proposed an interfacial criterion for spontaneous and forced engulfment of ceramic particles by an advancing solid/liquid interface. The sign of the interfacial force acting between a ceramic particle (c) and a solidification front (s) through the thin layer of a liquid (l) is determined by the sign of the quantity \u003cimg width=\"34\" height=\"20\" src=\"data:image/png;base64,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\" alt=\"image\"\u003e\u0026nbsp;(\u003cem\u003e\u0026Delta;\u0026sigma;\u003csub\u003ecls\u003c/sub\u003e\u003c/em\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e= \u003cem\u003e\u0026sigma;\u003csub\u003ecv\u003c/sub\u003e\u003c/em\u003e - \u003cem\u003e\u0026sigma;\u003csub\u003elv\u003c/sub\u003e\u003c/em\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e\u0026acute;\u0026nbsp;(0.08 + 1.22\u0026nbsp;\u0026acute;\u0026nbsp;\u003cem\u003ecos\u0026Theta;\u003csub\u003eclv\u003c/sub\u003e\u003c/em\u003e)\u0026nbsp; where\u0026nbsp;\u0026sigma;\u003csub\u003ecv\u003c/sub\u003e is the surface energy of the ceramic, \u003cem\u003e\u0026sigma;\u003csub\u003elv\u003c/sub\u003e\u003c/em\u003e is the surface tension of molten metal and \u0026Theta;\u003csub\u003eclv\u003c/sub\u003e is the contact angle of the molten metal on the ceramic substrate). The interfacial force is attractive, i.e., spontaneous engulfment of reinforcing particles by the solidification front is expected, if\u0026nbsp;\u003cimg width=\"64\" height=\"20\" src=\"data:image/png;base64,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\" alt=\"image\"\u003e. Kaptay\u003csup\u003e48\u003c/sup\u003e applied this criterion to a range of Al-ceramic systems (TiC, SiC, Al\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e3\u003c/sub\u003e, SiO\u003csub\u003e2\u003c/sub\u003e and TiB\u003csub\u003e2\u003c/sub\u003e) and found that the \u003cem\u003e\u0026Delta;\u0026sigma;\u003csub\u003ecls\u003c/sub\u003e\u003c/em\u003e values are positive for systems in which ceramic particles were observed to be pushed by the solidification front leading to particle segregation at the inter-grain area, which is undesirable for strength enhancement. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eDue to the formation of an ordered C\u003csub\u003eNbC\u003c/sub\u003e-like Mg layer on the exposed surfaces of NbC particles, the effective interface between the liquid Mg and particle (Mg(l)/NbC) becomes Mg(l)/Mg\u003csub\u003eterminal\u0026nbsp;\u003c/sub\u003eat Mg@NbC. This implies perfect wetting of the NbC substrate by the molten Mg with a contact angle approaching zero (\u0026Theta;\u003csub\u003eclv\u003c/sub\u003e=0). As a result, during solidification, the advancing Mg front interacts with the Mg@NbC particle to form a Mg(s)/Mg\u003csub\u003eterminal\u003c/sub\u003e interface rather than a direct Mg(s)/NbC interface.\u0026nbsp;As shown in Fig. 3\u003cstrong\u003ea\u003c/strong\u003e and Supplementary Fig. 12\u003cstrong\u003ec\u003c/strong\u003e, each terminal Mg atom exhibits 12 neighbours (four Mg atoms within the same plane, three Mg atoms in the 1\u003csup\u003est\u003c/sup\u003e Mg layer, four Nb atoms and one C in the underlying NbC layer). Although crystallographically distinct, this face-centred-cubic-like coordination provides each Mg atom in the terminal layer with a coordination number equivalent to that of bulk Mg. Given this structural similarity, the surface energy of the Mg-coated NbC particle can be reasonably approximated as that of pure Mg.\u0026nbsp;This leads to\u003cem\u003e\u0026nbsp;\u0026Delta;\u0026sigma;\u003csub\u003ecls\u003c/sub\u003e\u003c/em\u003e \u0026lt; 0, indicating spontaneous engulfment of NbC particles by the front during solidification of Mg(l)-Mg@NbC colloidal solution\u003csup\u003e48\u003c/sup\u003e. Furthermore, during solidification, Mg atoms at the advancing solidification front form Mg-Mg metallic bonds with the terminal Mg atoms on the surface of NbC particles, allowing the front to propagate through the Mg-coated NbC particles (Supplementary Fig.11). This behaviour indicates a weak correlation between the orientation of NbC particles and the solidification front, resulting in the engulfment of randomly oriented particles. Experimentally, no apparent orientation relationships between the NbC particles and the Mg matrix were observed (Supplementary Figs. 2, 4, 6).\u003c/p\u003e\n\u003cp\u003eIt is also notable that NbC possess a significantly higher shear modulus (~230 GPa\u003csup\u003e49\u003c/sup\u003e) than \u003cem\u003ein-situ\u003c/em\u003e formed precipitates\u003csup\u003e50-53\u003c/sup\u003e. These engulfed, chemically bonded high modulus NbC particles within the Mg matrix directly contribute to the effective strengthening\u003csup\u003e54\u003c/sup\u003e of the Mg matrix.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eIn conclusion, the combined atomistic-level experimental and theoretical study reveals the formation of an ordered Mg layer bonded to NbC particles (Mg@NbC), which is responsible for the observed spontaneous wetting and engulfment. The resulting material exhibits exceptional specific tensile strength and stiffness, surpassing many high-performance metals. To identify other metal-ceramic systems where the base molten metal spontaneously wets the ceramic nanoparticles, future design should specifically employ \u003cem\u003eab initio\u003c/em\u003e interface structure prediction and interfacial energy calculations. Beyond magnesium, these insights provide a blueprint for designing next-generation structural and functional metal-ceramic systems and scalable nanocolloid-based processing.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor contributions\u003c/h2\u003e\u003cp\u003eX.Y. and H.B.N conceptualised the project. They designed the experiments, prepared the materials, carried out the experimental work, processed the data, and performed the analysis. C.F. conducted the DFT calculations. S.N., M.K., T.T., and M.D. prepared the nanosized NbC powder feedstock. T.M. performed the micro-tensile testing. S.W. and Q.M.R. carried out the AC STEM/EELS investigations and data interpretation. F.T. and G.D.W. performed STEM/EDS and 4D-STEM analysis. All authors extensively discussed the data. X.Y., H.B.N., C.F., and S.W. wrote the manuscript, and all authors contributed to editing it.\u003c/p\u003e\u003ch2\u003eAcknowledgements\u003c/h2\u003e\u003cp\u003eX.Y. and H.B.N. acknowledge funding from the Engineering and Physical Sciences Research Council (EPSRC), grant number EP/W005042/1. The SuperSTEM Laboratory is the UK National Research Facility for Advanced Electron Microscopy, supported by EPSRC under grant number EP/W021080/1. M.K. acknowledges the fundings of the A-Step program grant number JPMJTR23R9 and of the KSAC program grant number 2024_21 from Japan Science and Technology Agency (JST). S.N. and M.K. also thank to the funding of Bilateral Joint Research, grant number JPJSBP120235704 from the Japan Society for the Promotion of Science (JSPS). X.Y. and H.B.N. thank CBMM (Companhia Brasileira de Metalurgia e Minera\u0026ccedil;\u0026atilde;o) for supporting a range of NbC powder feedstock. We thank Dr Qing Cai for assistance in microscopy characterisation.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eKwiatkowski da Silva, A.\u003cem\u003e et al\u003c/em\u003e. A sustainable ultra-high strength Fe18Mn3Ti maraging steel through controlled solute segregation and \u0026alpha;-Mn nanoprecipitation. \u003cem\u003eNature Communications\u003c/em\u003e\u003cstrong\u003e 13\u003c/strong\u003e, 2330 (2022).\u003c/li\u003e\n\u003cli\u003eNie, J. Precipitation and Hardening in Magnesium Alloys. \u003cem\u003eMetallurgical and Materials Transactions A\u003c/em\u003e\u003cstrong\u003e 43\u003c/strong\u003e, 3891\u0026ndash;3939 (2012).\u003c/li\u003e\n\u003cli\u003eShao, X. H., Yang, Z. Q. \u0026amp; Ma, X. L. 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The NbC particles with the average size (\u003cem\u003eD\u003csub\u003e50\u003c/sub\u003e\u003c/em\u003e) of 15 nm were produced using plasma spray chemical synthesis\u003csup\u003e55-57\u003c/sup\u003e coded as NbC\u003csub\u003enano\u003c/sub\u003e (Supplementary Figs. 14, 15).\u0026nbsp;To produce NbC\u003csub\u003enano\u003c/sub\u003e, a thermal plasma jet was first generated with a hybrid plasma spray system using Ar and H\u003csub\u003e2\u003c/sub\u003e gases. Raw Nb metal powders with an average diameter of 45 \u0026micro;m (Kojundo Chemical Co. Ltd., Japan) were then introduced into the plasma to form high temperature Nb vapour through complete vaporisation. CH\u003csub\u003e4\u003c/sub\u003e gas was also added to the plasma for carburisation of the Nb vapour to form NbC particles. The feed rate of the raw powders and the CH\u003csub\u003e4\u003c/sub\u003e gas flow rate were adjusted to control the NbC nanoparticle size and Nb/C ratio of the NbC solid solution. For particle size distribution measurements, using ImageJ 1.53k software\u003csup\u003e58\u003c/sup\u003e, 1500 particles were analysed for each batch. The NbC\u003csub\u003enano\u003c/sub\u003e and NbC\u003csub\u003esubmicron\u003c/sub\u003e powder feedstocks were cold pressed into 16 mm diameter pellets using a Specac Atlas 15T manual hydraulic press with 0.5 ton pressure. In the case of the NbC\u003csub\u003emicron\u003c/sub\u003e powder, 32 mm diameter pellets were produced by applying 1 ton pressure. The pressed NbC pellets were baked at 110\u0026deg;C for 12h and placed into a steel crucible containing molten Mg (99.95% purity) at 680\u0026deg;C with a protective gas mixture of nitrogen and R134a gas in the ratio of 12:1 (nitrogen flow at 3 L/min, R134a at 0.25 L/min), under ambient pressure, to achieve pressure-less infiltration. During infiltration, the entrapped air in the NbC precursor pellet escapes in the form of bubbles to the molten metal surface. The infiltrated pellets were then solidified at 0.3 K/s cooling rate in protective gas. A pure Mg reference sample was also solidified at the same cooling rate. The volume fraction of the NbC particles in the Mg-NbC materials was calculated based on the measured weight difference between the cold pressed NbC pellet and as-solidified Mg-NbC materials, as well as the density of the pure Mg (1.78 g/cm\u003csup\u003e3\u003c/sup\u003e) and the NbC phase (7.8 g/cm\u003csup\u003e3\u003c/sup\u003e). The volume fraction of the NbC phase in as-solidified Mg-NbC\u003csub\u003enano\u003c/sub\u003e, Mg-NbC\u003csub\u003esubmicron\u003c/sub\u003e, and Mg-NbC\u003csub\u003emicron\u003c/sub\u003e samples were 12.2 vol%, 38.7 vol%, and 53.8 vol%, respectively. A summary of the materials information is provided in Supplementary Table 2.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMechanical characterisation.\u003c/strong\u003e The micro-tensile specimens from as-solidified Mg-NbC\u003csub\u003enano\u003c/sub\u003e and Mg-NbC\u003csub\u003esubmicron\u003c/sub\u003e materials were prepared using a Thermo Fisher Scientific Scios 2 DualBeam focused ion beam-scanning electron microscope (FIB-SEM) and tested using a FemtoTools FT-NMT04 IN-SITU Nanoindentor under Field Emission-SEM (FE-SEM) observation by Scios 2 (Supplementary Fig. 16). The specimens were sectioned, lifted-out from the as-solidified Mg-NbC samples and then attached to a tungsten needle by Pt deposition into a prefabricated hole whose size conforms to the shape of the lifted sample. This was the fixed side in the tensile testing rig. The specimen was shaped into a dog-bone geometry with rectangular cross section (~10\u0026nbsp;mm gauge length and 12\u0026nbsp;mm\u003csup\u003e2\u003c/sup\u003e cross sectional area). The dog-bone specimen was attached to a Si gripper that connected to a microforce sensing probe (FT-S200\u0026rsquo;000) within FT-NNMT04. The micro-tensile test was performed in the displacement control mode and a strain rate of 1\u0026acute;10\u003csup\u003e-4\u003c/sup\u003e s\u003csup\u003e-1\u003c/sup\u003e. The video recording of the \u003cem\u003ein-situ\u003c/em\u003e tensile tests is presented in supplementary files (Supplementary Videos 1-3).\u003c/p\u003e\n\u003cp\u003eThe macro-tensile tests of the as-solidified Mg-13vol%NbC\u003csub\u003emicron\u003c/sub\u003e material and reference pure Mg were conducted on a Instron 5500 Universal Electromechanical Testing System with a constant cross head speed of 0.225 mm/min (2\u0026times;10\u003csup\u003e\u0026minus;4\u003c/sup\u003e s\u003csup\u003e\u0026minus;1\u003c/sup\u003e initial strain rate) and the results are shown in Supplementary Note Fig. 2\u003cstrong\u003ec\u003c/strong\u003e.\u003c/p\u003e\n\u003cp\u003eA Micro Materials NanoTest ALPHA with a Berkovich tip was used for nanoindentation tests with load-control to a maximum load of 100 mN with a 6.7 mN/s loading rate, held for 10 s, and unloaded at 6.7 mN/s. Hardness and elastic modulus are evaluated from the load-indentation depth curves.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMicrostructure observations.\u003c/strong\u003e A Zeiss Crossbeam 340 SEM and Thermo Fisher Scientific Talos F200X were used to investigate the microstructure of the NbC powder feedstock and the Mg-NbC samples. Scanning transmission electron microscopy (STEM) images and energy dispersive x-ray spectroscopy (EDS) elemental maps were collected using the Talos F200X instrument.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAtomic-resolution STEM imaging and electron energy loss spectroscopy (EELS) mapping were conducted using an aberration corrected Nion UltraSTEM100 working at 100 kV. The microscope is equipped with a cold-FEG emitter with 0.3 eV native energy spread. With a fifth-order probe aberration corrector, the microscope optics can be configured to enable a probe size of \u0026lt; 1 \u0026Aring; at 100 kV with a convergence semi-angle of 30 mrad and a probe current of 30 pA in the conditions used for these experiments. The semi-angular ranges for high-angle annular-dark-field (HAADF), medium-angle annular-dark-field (MAADF) images and annular-bright-field (ABF) images were 89 -195 mrad,\u0026nbsp;52-89 mrad (or 30-65 mrad when acquired simultaneously with ABF images), and 10-30 mrad, respectively. Electron energy loss spectra were acquired on a Gatan Enfina spectrometer that is retrofitted with a Quantum Detectors Merlin EELS hybrid pixel camera. EELS spectrum images (SIs) were acquired in \u0026ldquo;event-streamed\u0026rdquo; mode using a 36 mrad collection semi-angle. Leveraging the instrument\u0026rsquo;s exceptional stability, characterised by a minor sample drift under experimental conditions, multiple consecutive scans with short pixel dwell times (3 or 5 ms/pixel) were accumulated. This approach enabled sufficient signal acquisition while minimizing noise and sample damage through repeated acquisitions. Prior to data processing, the EELS SI dataset was denoised \u003cem\u003evia\u003c/em\u003e the built-in principal component analysis (PCA) function in Gatan Microscopy Suite 3.6 (GMS 3.6), with careful inspection of residuals to ensure artifact-free reconstruction. Notably, the near-ideal Poisson noise characteristics of data collected using next generation hybrid pixel detectors make them particularly well-suited for PCA-based denoising, enabling enhanced signal extraction with minimal artifact introduction\u003csup\u003e59\u003c/sup\u003e. EELS elemental maps were generated in two ways. For SIs containing the Nb \u003cem\u003eM\u003c/em\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003eedges (205 eV) and C \u003cem\u003eK\u003c/em\u003e (284 eV) in close proximity, we used model-based EELS quantification function in GMS 3.6 to separate the two signal components for elemental mapping. This method was applied to create Fig. 1\u003cstrong\u003eb\u003c/strong\u003e,\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003eSupplementary Fig. 14\u003cstrong\u003ed\u003c/strong\u003e and Fig. 15\u003cstrong\u003ed\u003c/strong\u003e, and the C \u003cem\u003eK\u003c/em\u003e map in Fig. 3\u003cstrong\u003ec\u003c/strong\u003e. For the Mg \u003cem\u003eK\u003c/em\u003e (1305 eV, in Fig. 3\u003cstrong\u003ec\u003c/strong\u003e) and Nb \u003cem\u003eL\u003csub\u003e2,3\u003c/sub\u003e\u003c/em\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003e(2465 eV, in Fig. 3c, Supplementary Fig. 14\u003cstrong\u003ee\u003c/strong\u003e and Fig. 15\u003cstrong\u003ee\u003c/strong\u003e) edges, we first subtracted a decaying background preceding each edge using a fitted power-law function and then integrated the EELS edge intensity over a 50 eV window from each edge onset. EELS map intensities are shown using a false colour scale, where low intensity indicates lower relative elemental concentration, and higher contrast reflects a relative increase in concentration. We note that two consecutive SIs were acquired in the same region in Fig. 3\u003cstrong\u003ec\u003c/strong\u003e to cover a wide energy range involving all the aforementioned core-loss edges, while only C \u003cem\u003eK\u003c/em\u003e, Nb \u003cem\u003eL\u003csub\u003e2,3\u003c/sub\u003e\u003c/em\u003e and Mg \u003cem\u003eK\u003c/em\u003e were selected for illustration in the main text.\u003c/p\u003e\n\u003cp\u003eCross-sections of the bulk samples were prepared using standard metallographic methods with the oil-based diamond suspensions. TEM specimens from the Mg-NbC samples were initially sliced from the bulk and ground to a thickness of ~100 \u0026micro;m, followed by dimpling using a Gatan dimple grinder system and subsequent thinning using ion milling with a Gatan PIPS 695 instrument that operated at 3-5 kV and beam angles of 3-5\u0026deg;. To remove damaged layers and any amorphous structure on the TEM foil surface, a final polishing step was performed at 1 kV with Ar⁺\u0026nbsp;ions at a 7\u0026deg; incident beam angle. Electron backscattered diffraction (EBSD) was performed to characterise the grain size of Mg in Mg-NbC samples. Specimens were placed in the Tescan Magna UHR-SEM tilted 70\u0026deg; from the horizontal plane towards the EBSD camera with a 30 kV electron beam, 13 nm spot size and 80-100 nm step size. The 4D-STEM based orientation/phase mapping was applied to produce crystallographic maps of the Mg-NbC\u003csub\u003enano\u003c/sub\u003e specimen at high resolution using a Talos F200X and NanoMegas ASTAR system at 200 kV, 2 nm step size. The data analysis was conducted by ATEX 5.0 software (Academic Edition)\u003csup\u003e60\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003eThe X-ray diffraction (XRD) spectrum for Mg-13vol%NbC\u003csub\u003emicron\u003c/sub\u003e sample was acquired using a Bruker D8 ADVANCE XRD diffractometer with a Cu K\u003csub\u003ea\u003c/sub\u003e (l= 0.1542 nm) radiation source, and the results are shown in Supplementary Note Fig. 2\u003cstrong\u003eb\u003c/strong\u003e. The candidate phases for matching are selected from Powder Diffraction File\u0026trade; (PDF\u003csup\u003e\u0026reg;\u003c/sup\u003e) database.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eDFT calculations\u003c/strong\u003e. The present \u003cem\u003eab initio\u003c/em\u003e molecular dynamics (AIMD) study employs the first-principles code VASP (Vienna \u003cem\u003eAb initio\u003c/em\u003e Simulation Package)\u003csup\u003e61\u003c/sup\u003e that utilizes the periodic boundary conditions (PBC).\u0026nbsp;Supercells were built for modelling the interfaces between liquid Mg and NbC substrates. NbC {001} substrate has an equal number of Nb and C atoms at the surface, being electronically neutral and non-polar. The number of liquid Mg atoms for the systems is fixed to be 300, while the number of Nb atoms and C atoms are fixed to be 72. A tetragonal supercell was created with\u0026nbsp;\u003cem\u003ea\u003c/em\u003e = 3\u003cem\u003ea\u003c/em\u003e\u003cem\u003e\u003csub\u003e0\u003c/sub\u003e\u003c/em\u003e\u003csub\u003e\u0026nbsp;\u003c/sub\u003efor the Mg(l)/NbC\u003csub\u003e{001}\u003c/sub\u003e interface, where\u0026nbsp;\u003cem\u003ea\u003c/em\u003e\u003cem\u003e\u003csub\u003e0\u003c/sub\u003e\u003c/em\u003e is the length of the axis of the conventional NbC cell with consideration of the thermal expansion at the simulation temperature\u003csup\u003e62\u003c/sup\u003e. The length of the\u0026nbsp;\u003cem\u003ec\u003c/em\u003e-axis is determined by the thickness of the NbC slab and the volume of the Mg atoms with the density at the simulation temperature\u003csup\u003e62\u003c/sup\u003e. The built supercells are summarized in Supplementary Table 3 and the related configurations are shown in Supplementary Fig. 17\u003cstrong\u003ea\u003c/strong\u003e. To avoid artificial interface interactions, a space of about 2.0 \u0026Aring; was made between the substrate atoms and the liquid Mg atoms.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eVASP employs the electronic density-functional theory (DFT) within the projector-augmented wave framework\u003csup\u003e63\u003c/sup\u003e. The generalised gradient approximation (GGA-PBE) was used for the exchange and correlation terms\u003csup\u003e64\u003c/sup\u003e. The cut-off energy for the \u003cem\u003eab initio\u003c/em\u003e molecular dynamics simulations is 320.0 eV and Г-point in the Brillouin zone is used as there is a lack of symmetry in the liquid/solid interfaces\u003csup\u003e61, 65\u003c/sup\u003e. The simulation temperature is set to be 1000 K.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eA two-step approach was used: first AIMD simulations were performed with the substrate atoms fixed for about 300 steps (1.5 femtosecond (fs) per step). Then, the AIMD simulations are continued with relaxation of all the atoms. The simulations revealed thermal equilibration after about 1 picosecond (ps) (see Supplementary Fig. 17). This approach avoids risks of collective movements of atoms during the AIMD simulations\u003csup\u003e45\u003c/sup\u003e.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003cstrong\u003eMethods References\u003c/strong\u003e\u003c/p\u003e\n\u003col start=\"55\"\u003e\n \u003cli\u003eKambara, M.\u003cem\u003e\u0026nbsp;et al\u003c/em\u003e. Nano-composite Si particle formation by plasma spraying for negative electrode of Li ion batteries. \u003cem\u003eJ. Appl. Phys.\u003c/em\u003e\u003cstrong\u003e\u0026nbsp;115\u003c/strong\u003e, 143302 (2014).\u003c/li\u003e\n \u003cli\u003eKambara, M., Huang, H. \u0026amp; Yoshida, T. in \u003cem\u003eAdvanced Plasma Technology\u0026nbsp;\u003c/em\u003e401\u0026ndash;419 (Wiley-VCH, ed., 2008).\u003c/li\u003e\n \u003cli\u003eYoshida, T. Toward a new era of plasma spray processing. \u003cem\u003ePure Appl. Chem.\u003c/em\u003e \u003cstrong\u003e78\u003c/strong\u003e, 1093\u0026ndash;1107 (2006).\u003c/li\u003e\n \u003cli\u003eSchneider, C. A., Rasband, W. S. \u0026amp; Eliceiri, K. W. NIH Image to ImageJ: 25 years of image analysis. \u003cem\u003eNature Methods\u003c/em\u003e\u003cstrong\u003e\u0026nbsp;9\u003c/strong\u003e, 671\u0026ndash;675 (2012).\u003c/li\u003e\n \u003cli\u003eHaberfehlner, G.\u003cem\u003e\u0026nbsp;et al\u003c/em\u003e. Benefits of direct electron detection and PCA for EELS investigation of organic photovoltaics materials. \u003cem\u003eMicron\u003c/em\u003e\u003cstrong\u003e\u0026nbsp;140\u003c/strong\u003e, 102981 (2021).\u003c/li\u003e\n \u003cli\u003eBeausir B. \u0026amp; Eundenberger J.-J. Analysis Tools for Electron and X-ray diffraction, ATEX-software. (2017).\u003c/li\u003e\n \u003cli\u003eKresse, G. \u0026amp; Hafner, J. Ab initio molecular-dynamics simulation of the liquid-metal--amorphous-semiconductor transition in germanium. \u003cem\u003ePhys. Rev. B\u003c/em\u003e\u003cstrong\u003e\u0026nbsp;49\u003c/strong\u003e, 14251\u0026ndash;14269 (1994).\u003c/li\u003e\n \u003cli\u003eTirumalasetty, G. K.\u003cem\u003e\u0026nbsp;et al\u003c/em\u003e. Characterization of NbC and (Nb,Ti)N nanoprecipitates in TRIP assisted multiphase steels. \u003cem\u003eActa Materialia\u003c/em\u003e\u003cstrong\u003e\u0026nbsp;59\u003c/strong\u003e, 7406\u0026ndash;7415 (2011).\u003c/li\u003e\n \u003cli\u003eBl\u0026ouml;chl, P. E. Projector augmented-wave method. \u003cem\u003ePhys. Rev. B\u003c/em\u003e\u003cstrong\u003e\u0026nbsp;50\u003c/strong\u003e, 17953\u0026ndash;17979 (1994).\u003c/li\u003e\n \u003cli\u003ePerdew, J. P., Burke, K. \u0026amp; Ernzerhof, M. Generalized Gradient Approximation Made Simple. \u003cem\u003ePhys. Rev. Lett.\u003c/em\u003e\u003cstrong\u003e\u0026nbsp;77\u003c/strong\u003e, 3865\u0026ndash;3868 (1996).\u003c/li\u003e\n \u003cli\u003eMonkhorst, H. J. \u0026amp; Pack, J. D. Special points for Brillouin-zone integrations. \u003cem\u003ePhys. Rev. B\u003c/em\u003e\u003cstrong\u003e\u0026nbsp;13\u003c/strong\u003e, 5188\u0026ndash;5192 (1976).\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"nature-portfolio","isNatureJournal":true,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"","title":"Nature Portfolio","twitterHandle":"","acdcEnabled":false,"dfaEnabled":false,"editorialSystem":"ejp","reportingPortfolio":"","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-7589727/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7589727/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eWe report a simple, scalable route to produce ultrahigh-strength magnesium (Mg) \u003cem\u003evia\u003c/em\u003esolidification of a colloidal solution containing nanoscale niobium carbide (NbC) particles suspended in liquid magnesium (Mg(l)). A single-atom-level investigation reveals that NbC exhibits excellent spontaneous wetting with molten Mg, driven by the formation of an ordered layer of Mg atoms strongly bonded to the carbon atoms on the NbC {001} surface. This creates a novel type of Mg-coated NbC (Mg@NbC) particles in liquid Mg and is referred to as Mg(l)-Mg@NbC nanocolloid. This unique and spontaneous wetting behaviour enables uniform nanoparticle dispersion in the molten Mg without external fields, and in the solidified Mg matrix without the need for thermomechanical processing. The resulting NbC dispersoids act as coherent, hard reinforcement phases, significantly strengthening the Mg matrix. As a result, the Mg-NbC material exhibits ultrahigh tensile strength and stiffness, surpassing those of all previously reported Mg alloy systems.\u003c/p\u003e","manuscriptTitle":"Ultrahigh strength magnesium via solidification of nanocolloid","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-17 12:40:46","doi":"10.21203/rs.3.rs-7589727/v1","editorialEvents":[],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"nature-communications","isNatureJournal":true,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"NCOMMS","sideBox":"Learn more about [Nature Communications](http://www.nature.com/ncomms/)","snPcode":"","submissionUrl":"https://mts-ncomms.nature.com/","title":"Nature Communications","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"ejp","reportingPortfolio":"Nature Communications","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"0163a05d-c242-4b37-9905-8319430b36d4","owner":[],"postedDate":"October 17th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[{"id":56365799,"name":"Physical sciences/Materials science/Nanoscale materials/Structural properties"},{"id":56365800,"name":"Scientific community and society/Business and industry/Engineering/Mechanical engineering"}],"tags":[],"updatedAt":"2026-03-27T14:20:23+00:00","versionOfRecord":[],"versionCreatedAt":"2025-10-17 12:40:46","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7589727","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7589727","identity":"rs-7589727","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}