Research on the influence of aging treatment on the folding behavior and mechanical behavior of rolling silk in titanium alloy wire

Research on the influence of aging treatment on the folding behavior and mechanical behavior of rolling silk in titanium alloy wire | 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 Research on the influence of aging treatment on the folding behavior and mechanical behavior of rolling silk in titanium alloy wire Yue Qi, Yinxiang Chai, Dongmei Chen, Kun Zhang, Hongye Sun, Quanshi Cheng, and 4 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6252489/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract As a critical component in the field of aerospace assembly, the mechanical and processing properties of titanium alloy wire are pivotal indicators determining the performance of fasteners. In this research, Ti6Al4V wire, post-drawing, was subjected to solution treatment at 960 ± 8°C for 1 hour, followed by aging treatments at 540°C, 560°C, 580°C, and 620°C. The microstructural characteristics and mechanical behavior of the wire post-heat treatment were thoroughly characterized. The findings revealed that the solution and aging treatments significantly enhanced the mechanical properties of the Ti6Al4V wire. Specifically, the tensile yield strength increased from 882 MPa to 1060 MPa, and the average axial compressive performance, Rpc0.2, improved from 859 MPa to 1020 MPa. It was observed that the resistance to thread fold formation, as well as the tensile and shear properties of the bolts, gradually declined with increasing aging temperatures. However, it was also noted that lower shear performance effectively mitigated the occurrence of rolling-induced folding defects during processing. The research demonstrated that an optimized heat treatment regimen can effectively address the issue of rolling-induced folding in titanium alloy wires, thereby enhancing the mechanical performance of fasteners. Physical sciences/Materials science/Materials for devices Physical sciences/Materials science/Structural materials Titanium wires Aging treatment Material strength Rolling-induced folding Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Introduction Titanium alloys are widely used in the aerospace industry due to their advantages such as low density, high specific strength, and excellent corrosion resistance. Titanium alloy bolts are typical representatives of lightweight, high-strength fasteners. Ti6Al4V alloy, a material commonly used in the aviation industry, exhibits an excellent strength-to-weight ratio, a low thermal expansion coefficient, and good corrosion resistance. Aluminum, as an α-phase stabilizing element, and vanadium, as a β-phase stabilizing element, endow Ti6Al4V alloy with a dual-phase microstructure at room temperature. This microstructure, which combines the deformation characteristics of both α and β phases, makes it a critical material for aircraft fasteners. At the same time, as essential load-bearing components of aircraft, fasteners must ensure the repeated assembly and disassembly of major aircraft parts. During service, they may be subjected to a range of loads and forces, including compression, tension, bending, torsion, and pressure. Therefore, ensuring reliable mechanical properties of fasteners is key to their performance. Previous studies demonstrated that heat treatment processes significantly altered the microstructure of titanium alloys 1-5 . After solution treatment, titanium alloys formed supersaturated solid solutions, which greatly enhanced their strength. Subsequent aging treatment allowed the precipitation of dispersed phases from the supersaturated solid solution, achieving a strengthening effect while also improving plasticity and toughness. After solution treatment, the tensile strength decreased with increasing temperature, while plasticity remained relatively unchanged. Impact toughness and absorbed energy increased with rising temperature 6,7 . Cold-rolled alloy wires exhibited lower tensile and yield strength after heat treatment, whereas hot-drawn alloy wires showed higher tensile and yield strength post-heat treatment 8 . Meanwhile, the thread serves as a critical structural component of fasteners, playing a pivotal role in achieving their fastening and connecting functions. In the aerospace industry, the most commonly employed method for forming threads on bolts is thread rolling, which is also referred to as thread forming in the manufacturing process of fasteners. Current research on bolt folding primarily focuses on various aspects, including thread rolling parameters, stress distribution, end structures, and microstructural properties. Research has shown that processing parameters were the primary factors influencing the quality of the final product 9,10 . The rolling speed and the number of rolling passes had varying degrees of impact on the microstructure and mechanical properties of bolts 11,12 . For instance, bolts made from AISI 4340 alloy steel exhibited a significant reduction in internal microcracks and other microdefects after heat treatment. These heat-treated bolts could endure nearly 40,000 cycles before fracture, representing a fourfold improvement compared to untreated bolts. Similarly, in AlSi4MgMn and AlSi9MgMn alloys, the transformation of the microstructure from a continuous eutectic network to a spheroidized Si morphology enhanced the energy absorption capacity of the alloys, thereby improving their tensile and shear strength 13,14 . Heat treatment also induced changes in the microstructure of alloys. For example, in alloy steels, the transformation from pearlite to austenite after heat treatment elevated the strength grade of bolts from 8.8 to 9.8. In titanium alloys, the microstructure shifted from αʹ martensite to a fully stabilized α+β lamellar structure. Annealed samples demonstrated superior plasticity and work-hardening rates during processing, with their energy absorption capacity increasing by 74.7% compared to non-annealed samples. Additionally, microcracks were significantly mitigated due to these microstructural changes 15-18 . This research focused on Ti-6Al-4V alloy wires subjected to solution treatment, followed by aging treatment at different temperatures. The axial and radial mechanical properties of Ti-6Al-4V fasteners were investigated using digital image correlation (DIC) technology. Additionally, the microstructure of the fasteners was characterized using field emission scanning electron microscopy (FESEM) combined with electron backscatter diffraction (EBSD) technology. By adjusting the aging temperature, the thread rolling folding behavior of the bolts was further explored. 1 Experimental materials and methods 1 Experimental materials and methods 1.1 Experimental materials The subject of this research was Ti-6Al-4V alloy wire, which conformed to the material standard 11-CL-52A and had a diameter of 5.03 mm. The chemical composition of the alloy was detailed in Table 1. C N Fe Al V O Ti 0.014 0.004 0.17 5.96 4.1 0.1 Residual Table 1 Chemical composition of Ti6Al4V alloy (mass fraction, Wt %) 1.2 Ti6Al4V wire solution aging treatment Based on the phase transformation temperature of Ti-6Al-4V alloy, the solution treatment for the wire was selected as 960°C for 1 hour, followed by water quenching. The aging treatments were conducted at 540°C, 560°C, 580°C, and 620°C for 4 hours, respectively. 1.3 Microstructure characterization The Ti-6Al-4V wire before and after heat treatment, as well as the bolt samples after thread rolling, were mounted and ground using sandpaper with grit sizes ranging from 240 to 2000. After grinding, the samples were polished. The polished samples were then etched using a corrosive solution for 30 to 40 seconds. Electron backscatter diffraction (EBSD) analysis was performed on the bolt wire using a scanning electron microscope, with a step size of 0.4 µm. The subsequent EBSD data were analyzed using Aztec Crystal software to generate pole figures and inverse pole figures. Additionally, transmission electron microscopy (TEM) samples were prepared from the wire using a Thermo Scientific Scios-2 FIB-SEM system. The microstructures of the samples were observed and analyzed using a Thermo Fisher Talos F200X transmission electron microscope at an accelerating voltage of 200 kV. 1.4 mechanical property measurement Tensile and compression tests were conducted using the Instron 8862 electro-hydraulic testing machine integrated with a digital image correlation (DIC) system. To enable DIC imaging, a random pattern with suitable dimensions and resolution was applied as a strain marker on the sample surface. In this investigation, black paint was uniformly sprayed onto a white coating on the sample surface using a spray can to create a distinct spot pattern for subsequent data analysis using Instron's DIC Replay software. 1.5 Roll forming scheme The specific rolling forming parameters were shown in Table 2. 1 rpm (r/min) 15 feed rate (mm/r) 0.07 Table 2 Roll forming scheme 2 Realization results and theoretical analysis 2.1 Microstructure characteristics of Ti6Al4V alloy wire before and after heat treatment The microstructure of Ti6Al4V wire before and after solution treatment was shown in Fig 2. Observations revealed that as the temperature increased, the equiaxed α grains exhibited a growth trend. When the aging temperature was within the range of 540-580°C, the microstructures were similar, showing only a slight growth of the α phase. This indicated that variations in the aging temperature within this range had little effect on the primary α phase, with the morphology and volume fraction of the primary α phase being primarily determined by the solution treatment. However, when the aging temperature was increased to 620°C, the microstructure underwent significant changes, with both the size and morphology of the α phase being noticeably altered. This suggested that at 620°C, the conditions favored the growth of the α phase while also promoting the transformation of the unstable β phase into secondary α phase and stable β phase, which would lead to a reduction in strength. The orientation distribution of Ti6Al4V wire in the as-drawn state and after aging treatment at 540°C for 4 hours was shown in Fig 3. EBSD analysis revealed that during the drawing deformation process, the α-phase grains dominated the microstructure, as illustrated in Fig 3a, with most grains exhibiting moderate orientation errors. During deformation, the α grains rotated along the axial direction to preferred orientations, aligning with the (0110) and (1210) crystal planes. After solution treatment, the elongated α grains transformed into a bimodal microstructure, consisting of primary α and transformed β structures. The primary α phase exhibited an equiaxed morphology with an average diameter of approximately 5 μm, while the transformed β structure was composed of α/β lamellar structures thinner than 1 μm, as shown in Fig 3b. The texture and grain orientations formed during the deformation process gradually disappeared. According to the Hall-Petch relationship, the smaller α grain size and thinner α/β lamellar structures contributed to enhancing the strength of the alloy. The bright-field TEM results indicated that after solution treatment, the material primarily exhibited a bimodal microstructure. Within this structure, the equiaxed α phase had a diameter of approximately 2–5 μm (consistent with the EBSD analysis), while the α/β lamellar structure typically featured layer thicknesses ranging from 100 to 200 nm, as shown in Fig 4. Considering that the α/β lamellar structure formed as a result of the cooling of the high-temperature stable β phase, during which the diffusion of elements and atoms was incomplete, we proposed that dislocations were primarily concentrated within the α lamellae. In contrast, the β lamellae, having undergone no significant structural transformation, contained fewer dislocations and lattice distortions. 2.2 Mechanical behavior of Ti6Al4V wire The mechanical behavior of Ti6Al4V wire was shown in Fig 5. It could be observed that after solution and aging treatment, the axial tensile strength increased from 1060 MPa in the as-drawn state to 1200 MPa, while the axial compressive yield strength (Rpc0.2) increased from 862 MPa to 1020 MPa. By comparison, it was evident that the mechanical properties were significantly improved after the solution and aging treatment. 2.3 Rolling folding behavior and mechanical resistance of Ti6Al4V wire Threads were rolled on wire blanks treated under different aging conditions according to a determined rolling scheme. The number of test samples for each group was 5 pieces (3 pieces for tensile testing), and the folding depth was observed using the metallographic method. The thread forming effect after rolling is shown in Fig 6, and the statistical data are presented in Table 3. The rolling folding depth significantly decreased as the aging temperature increased. When the temperature was raised from 540°C to 560°C, the folding depth decreased from 199 μm to 113 μm, representing a reduction of 43%. The number of samples without folding increased from 1 to 4, and the qualification rate was significantly improved. When the aging temperature reached 580°C, the rolling folding depth further decreased to 90 μm, representing only a 20% reduction compared to the folding depth at 560°C. When the aging temperature reached 620°C, the rolling folding issue was completely eliminated, and no folding problems occurred. scheme aging treatment Rolling fold situation 1-1 540℃x4h，Ar 1 piece without folding; 2 pieces guide end folding 199μm; 1 piece folded through tooth type; One tooth top folded 180μm 1-2 560℃x4h，Ar 1 tooth crest folded 113μm; the other 4 teeth without fold 1-3 580℃x4h，Ar One tooth top fold 90μm; The remaining 4 pieces have no folding 1-4 620℃x4h，Ar 5 pieces are not folded Table 3 Mechanical properties and rolling folding of titanium alloy bolts under different aging regimes As shown in Fig. 7, the mechanical behavior of the bolt after rolling forming was statistically analyzed. When the aging temperature increased from 540 °C to 580 °C, the tensile strength and shear strength did not change significantly. It was determined that aging in this temperature region had little effect on the performance. With the increase of aging temperature, when the temperature reached more than 620 °C, the mechanical properties decreased significantly, and the tensile properties decreased by nearly 1.5 KN, with a reduction of 6%. It was observed that as the aging temperature increased, the α phase tended to grow gradually, accompanied by a decrease in strength. A slight reduction in strength helped avoid the phenomenon of rolling wire folding. 3 Conclusions This research investigated the effects of aging treatment on the mechanical behavior and thread rolling folding behavior of Ti6Al4V wire. By analyzing the properties before and after aging, as well as the thread rolling folding behavior post-processing, the following conclusions were obtained: (1) The microstructure of the solution-treated and aged state consisted of equiaxed α grains uniformly distributed on the β matrix. The grains became finer, and the smaller α grain size and thinner α/β lamellar structure contributed to enhancing the alloy's strength. (2) When the mechanical properties of the wire after solution treatment and aging were compared, it was found that the solution treatment and aging process significantly increased the dislocation density of the α phase, markedly improving the tensile and compressive properties of the wire. (3) By comparing and analyzing the relationship between mechanical properties, microstructure, and folding behavior at various aging temperatures, it was observed that within the temperature range of 540-580°C, the grain size of the equiaxed α phase was the primary factor influencing the thread rolling folding behavior. After aging at 620°C, the thread rolling folding behavior was influenced by both the grain size of the equiaxed α phase and the mechanical properties, but the grain size remained the dominant factor. (4) When higher mechanical properties were required, aging treatment at 560-580°C was recommended. When lower mechanical properties were acceptable, aging at 620°C was preferable, as it resulted in favorable thread morphology and ensured the product's service performance. Declarations Date availability The data that support the findings of this study are within the Article, or available from the corresponding author upon reasonable request. Author contributions statement Yue Qi: Writing–original draft, Conceptualization. Shuo Zhao: Investigation, Conceptualization. Yinxiang Chai: Data curation. Dongmei Chen: Data curation. Kun Zhang: Data curation. Hongye Sun: Data curation. Quanshi Cheng: Formal analysis. Wensheng Li: Investigation. Zhongliang Lin: Investigation. Han Zhang: Investigation. Competing interests The authors declare no competing interests. Additional information Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. References Ren, Y. et al. Enhancing the energy absorption capacity of Ti–6Al–4V lattice structure manufactured by additive manufacturing through β-annealing [J]. Journal of Materials Research and Technology, 35 2369–2376. (2025). https://doi.org/10.1016/j.jmrt.2025.01.214 (2025). Wang, C. et al. Enhanced tensile properties of laser powder-bed fusion-manufactured TA15 alloy across a wide temperature range [J]. Materials Science & Engineering A, 926 147950–147950. (2025). https://doi.org/10.1016/j.msea.2025.147950 (2025). Cui, Y. A. et al. 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Optimum Thread Rolling Process that Improves SCC Resistance [J]. J. ASTM Int. 3 (7). https://doi.org/10.1520/JAI13414 (2006). Ren, Y. et al. Enhancing the energy absorption capacity of Ti–6Al–4V lattice structure manufactured by additive manufacturing through β-annealing [J]. J. Mater. Res. Technol. 35 , 2369–2376. https://doi.org/10.1016/j.jmrt.2025.01.214 (2025). Seo, S. et al. Improving fatigue life and toughness in electron beam welded Ti–6Al–4V achieved through beta heat treatment for microstructure uniformity [J]. J. Mater. Res. Technol. 35 , 869–880. https://doi.org/10.1016/j.jmrt.2025.01.055 (2025). Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted 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. 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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-6252489","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":441171794,"identity":"aeddb311-99fe-441a-95d5-e940ac3e699c","order_by":0,"name":"Yue Qi","email":"","orcid":"","institution":"Aerospace Precision Products Inc., Ltd","correspondingAuthor":false,"prefix":"","firstName":"Yue","middleName":"","lastName":"Qi","suffix":""},{"id":441171795,"identity":"25d04ded-cfcc-457e-aa29-ed4954af04ba","order_by":1,"name":"Yinxiang Chai","email":"","orcid":"","institution":"Process of Shenyang Aerospace 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18:02:09","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":3939815,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eMicrostructure of Ti6Al4V wire (a) in original drawn state, (b) aged at 540℃-4h,(c) aged at560℃-4h, (d) aged at 580℃-4h,(e) aged at 620℃-4h.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"Fig.2.png","url":"https://assets-eu.researchsquare.com/files/rs-6252489/v1/373e796226c50c6e39efd41f.png"},{"id":80566471,"identity":"b4fda6e8-482e-4a37-ad37-7e38bc407ad1","added_by":"auto","created_at":"2025-04-14 18:02:09","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":2565393,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eOrientation distribution diagram of Ti6Al4V wire before and after solution treatment\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e(a) EBSD structure as drawn (b) EBSD structure after solution treatment at 540℃\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"Fig.3.png","url":"https://assets-eu.researchsquare.com/files/rs-6252489/v1/b45a22112a4b7c9bab6022b0.png"},{"id":80566086,"identity":"88284494-e810-4900-b3e8-8f7ffaa586ae","added_by":"auto","created_at":"2025-04-14 17:54:09","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":1921223,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eMicrostructure of Ti6Al4V silk after solid solution (a) α/β slat tissue (b) dislocation tissue in the slat\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"Fig.4.png","url":"https://assets-eu.researchsquare.com/files/rs-6252489/v1/b3f6e47decda027fa10cc74c.png"},{"id":80566898,"identity":"c35b4234-56ff-472e-8e2c-9a24b82b5480","added_by":"auto","created_at":"2025-04-14 18:10:09","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":538756,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eMechanical properties after solution treatment at 540℃\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e(a) tensile stress-strain curve (b) compressive stress-strain curve\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"Fig.5.png","url":"https://assets-eu.researchsquare.com/files/rs-6252489/v1/14d68354b8c8ae5995e2deb3.png"},{"id":80566089,"identity":"9a9d22cd-2ff0-4aa1-b63f-ada2a7fc61b1","added_by":"auto","created_at":"2025-04-14 17:54:09","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":4126868,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eMetallographic diagram of rolling effect of different aging systems (a) 540℃ aging, (b) 560℃ aging, (c) 580℃ aging, (d) 620℃ aging\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"Fig.6.png","url":"https://assets-eu.researchsquare.com/files/rs-6252489/v1/9f9c010e6cd640c2513cd712.png"},{"id":80566087,"identity":"bc92c6be-350e-4c25-b9ae-0a05031ccc34","added_by":"auto","created_at":"2025-04-14 17:54:09","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":525007,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eTensile and shear properties of bolts after thread rolling\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"Fig.7.png","url":"https://assets-eu.researchsquare.com/files/rs-6252489/v1/0c4a46aeb5c48dd77f06d25f.png"},{"id":81627924,"identity":"c9a0c840-a0f2-4e6f-bf05-2238a07b2504","added_by":"auto","created_at":"2025-04-29 10:47:01","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":14687816,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6252489/v1/71e8991d-c5fd-4a1d-a553-6c5aabf57ab6.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Research on the influence of aging treatment on the folding behavior and mechanical behavior of rolling silk in titanium alloy wire","fulltext":[{"header":"Introduction","content":"\u003cp\u003eTitanium alloys are widely used in the aerospace industry due to their advantages such as low density, high specific strength, and excellent corrosion resistance. Titanium alloy bolts are typical representatives of lightweight, high-strength fasteners. Ti6Al4V alloy, a material commonly used in the aviation industry, exhibits an excellent strength-to-weight ratio, a low thermal expansion coefficient, and good corrosion resistance. Aluminum, as an \u0026alpha;-phase stabilizing element, and vanadium, as a \u0026beta;-phase stabilizing element, endow Ti6Al4V alloy with a dual-phase microstructure at room temperature. This microstructure, which combines the deformation characteristics of both \u0026alpha; and \u0026beta; phases, makes it a critical material for aircraft fasteners. At the same time, as essential load-bearing components of aircraft, fasteners must ensure the repeated assembly and disassembly of major aircraft parts. During service, they may be subjected to a range of loads and forces, including compression, tension, bending, torsion, and pressure. Therefore, ensuring reliable mechanical properties of fasteners is key to their performance. Previous studies demonstrated that heat treatment processes significantly altered the microstructure of titanium alloys\u003csup\u003e1-5\u003c/sup\u003e. After solution treatment, titanium alloys formed supersaturated solid solutions, which greatly enhanced their strength. Subsequent aging treatment allowed the precipitation of dispersed phases from the supersaturated solid solution, achieving a strengthening effect while also improving plasticity and toughness. After solution treatment, the tensile strength decreased with increasing temperature, while plasticity remained relatively unchanged. Impact toughness and absorbed energy increased with rising temperature\u003csup\u003e6,7\u003c/sup\u003e. Cold-rolled alloy wires exhibited lower tensile and yield strength after heat treatment, whereas hot-drawn alloy wires showed higher tensile and yield strength post-heat treatment\u003csup\u003e8\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003eMeanwhile, the thread serves as a critical structural component of fasteners, playing a pivotal role in achieving their fastening and connecting functions. In the aerospace industry, the most commonly employed method for forming threads on bolts is thread rolling, which is also referred to as thread forming in the manufacturing process of fasteners. Current research on bolt folding primarily focuses on various aspects, including thread rolling parameters, stress distribution, end structures, and microstructural properties. Research has shown that processing parameters were the primary factors influencing the quality of the final product\u003csup\u003e9,10\u003c/sup\u003e. The rolling speed and the number of rolling passes had varying degrees of impact on the microstructure and mechanical properties of bolts\u003csup\u003e11,12\u003c/sup\u003e. For instance, bolts made from AISI 4340 alloy steel exhibited a significant reduction in internal microcracks and other microdefects after heat treatment. These heat-treated bolts could endure nearly 40,000 cycles before fracture, representing a fourfold improvement compared to untreated bolts. Similarly, in AlSi4MgMn and AlSi9MgMn alloys, the transformation of the microstructure from a continuous eutectic network to a spheroidized Si morphology enhanced the energy absorption capacity of the alloys, thereby improving their tensile and shear strength\u003csup\u003e13,14\u003c/sup\u003e. Heat treatment also induced changes in the microstructure of alloys. For example, in alloy steels, the transformation from pearlite to austenite after heat treatment elevated the strength grade of bolts from 8.8 to 9.8. In titanium alloys, the microstructure shifted from \u0026alpha;ʹ martensite to a fully stabilized \u0026alpha;+\u0026beta; lamellar structure. Annealed samples demonstrated superior plasticity and work-hardening rates during processing, with their energy absorption capacity increasing by 74.7% compared to non-annealed samples. Additionally, microcracks were significantly mitigated due to these microstructural changes\u003csup\u003e15-18\u003c/sup\u003e.\u003c/p\u003e\n\u003cp\u003eThis research focused on Ti-6Al-4V alloy wires subjected to solution treatment, followed by aging treatment at different temperatures. The axial and radial mechanical properties of Ti-6Al-4V fasteners were investigated using digital image correlation (DIC) technology. Additionally, the microstructure of the fasteners was characterized using field emission scanning electron microscopy (FESEM) combined with electron backscatter diffraction (EBSD) technology. By adjusting the aging temperature, the thread rolling folding behavior of the bolts was further explored.\u003c/p\u003e"},{"header":"1 Experimental materials and methods","content":"\u003cp\u003e\u003cstrong\u003e1 Experimental materials and methods\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.1\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eExperimental materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe subject of this research was Ti-6Al-4V alloy wire, which conformed to the material standard 11-CL-52A and had a diameter of 5.03 mm. The chemical composition of the alloy was detailed in Table 1.\u003c/p\u003e\n\u003cdiv\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 14.0049%;\"\u003e\n \u003cp\u003eC\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.0049%;\"\u003e\n \u003cp\u003eN\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.0049%;\"\u003e\n \u003cp\u003eFe\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.0049%;\"\u003e\n \u003cp\u003eAl\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.0049%;\"\u003e\n \u003cp\u003eV\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.0049%;\"\u003e\n \u003cp\u003eO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.9705%;\"\u003e\n \u003cp\u003eTi\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 14.0049%;\"\u003e\n \u003cp\u003e0.014\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.0049%;\"\u003e\n \u003cp\u003e0.004\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.0049%;\"\u003e\n \u003cp\u003e0.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.0049%;\"\u003e\n \u003cp\u003e5.96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.0049%;\"\u003e\n \u003cp\u003e4.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 14.0049%;\"\u003e\n \u003cp\u003e0.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 15.9705%;\"\u003e\n \u003cp\u003eResidual\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cstrong\u003eTable 1 Chemical composition of Ti6Al4V alloy (mass fraction, Wt %)\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.2\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eTi6Al4V wire solution aging treatment\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eBased on the phase transformation temperature of Ti-6Al-4V alloy, the solution treatment for the wire was selected as 960\u0026deg;C for 1 hour, followed by water quenching. The aging treatments were conducted at 540\u0026deg;C, 560\u0026deg;C, 580\u0026deg;C, and 620\u0026deg;C for 4 hours, respectively.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.3 Microstructure characterization\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe Ti-6Al-4V wire before and after heat treatment, as well as the bolt samples after thread rolling, were mounted and ground using sandpaper with grit sizes ranging from 240 to 2000. After grinding, the samples were polished. The polished samples were then etched using a corrosive solution for 30 to 40 seconds. Electron backscatter diffraction (EBSD) analysis was performed on the bolt wire using a scanning electron microscope, with a step size of 0.4 \u0026micro;m. The subsequent EBSD data were analyzed using Aztec Crystal software to generate pole figures and inverse pole figures. Additionally, transmission electron microscopy (TEM) samples were prepared from the wire using a Thermo Scientific Scios-2 FIB-SEM system. The microstructures of the samples were observed and analyzed using a Thermo Fisher Talos F200X transmission electron microscope at an accelerating voltage of 200 kV.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.4 mechanical property measurement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eTensile and compression tests were conducted using the Instron 8862 electro-hydraulic testing machine integrated with a digital image correlation (DIC) system. To enable DIC imaging, a random pattern with suitable dimensions and resolution was applied as a strain marker on the sample surface. In this investigation, black paint was uniformly sprayed onto a white coating on the sample surface using a spray can to create a distinct spot pattern for subsequent data analysis using Instron\u0026apos;s DIC Replay software.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e1.5 Roll forming scheme\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe specific rolling forming parameters were shown in Table 2.\u003c/p\u003e\n\u003cdiv\u003e\n \u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 57.9365%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42.0635%;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 57.9365%;\"\u003e\n \u003cp\u003erpm\u003c/p\u003e\n \u003cp\u003e(r/min)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42.0635%;\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 57.9365%;\"\u003e\n \u003cp\u003efeed rate\u003c/p\u003e\n \u003cp\u003e(mm/r)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 42.0635%;\"\u003e\n \u003cp\u003e0.07\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003eRoll forming scheme\u003c/strong\u003e\u003c/p\u003e"},{"header":"2 Realization results and theoretical analysis","content":"\u003cp\u003e\u003cstrong\u003e2.1 Microstructure characteristics of Ti6Al4V alloy wire before and after heat treatment\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe microstructure of Ti6Al4V wire before and after solution treatment was shown in Fig 2. Observations revealed that as the temperature increased, the equiaxed \u0026alpha; grains exhibited a growth trend. When the aging temperature was within the range of 540-580\u0026deg;C, the microstructures were similar, showing only a slight growth of the \u0026alpha; phase. This indicated that variations in the aging temperature within this range had little effect on the primary \u0026alpha; phase, with the morphology and volume fraction of the primary \u0026alpha; phase being primarily determined by the solution treatment. However, when the aging temperature was increased to 620\u0026deg;C, the microstructure underwent significant changes, with both the size and morphology of the \u0026alpha; phase being noticeably altered. This suggested that at 620\u0026deg;C, the conditions favored the growth of the \u0026alpha; phase while also promoting the transformation of the unstable \u0026beta; phase into secondary \u0026alpha; phase and stable \u0026beta; phase, which would lead to a reduction in strength.\u003c/p\u003e\n\u003cp\u003eThe orientation distribution of Ti6Al4V wire in the as-drawn state and after aging treatment at 540\u0026deg;C for 4 hours was shown in Fig 3. EBSD analysis revealed that during the drawing deformation process, the \u0026alpha;-phase grains dominated the microstructure, as illustrated in Fig 3a, with most grains exhibiting moderate orientation errors. During deformation, the \u0026alpha; grains rotated along the axial direction to preferred orientations, aligning with the (0110) and (1210) crystal planes. After solution treatment, the elongated \u0026alpha; grains transformed into a bimodal microstructure, consisting of primary \u0026alpha; and transformed \u0026beta; structures. The primary \u0026alpha; phase exhibited an equiaxed morphology with an average diameter of approximately 5 \u0026mu;m, while the transformed \u0026beta; structure was composed of \u0026alpha;/\u0026beta; lamellar structures thinner than 1 \u0026mu;m, as shown in Fig 3b. The texture and grain orientations formed during the deformation process gradually disappeared. According to the Hall-Petch relationship, the smaller \u0026alpha; grain size and thinner \u0026alpha;/\u0026beta; lamellar structures contributed to enhancing the strength of the alloy.\u003c/p\u003e\n\u003cp\u003eThe bright-field TEM results indicated that after solution treatment, the material primarily exhibited a bimodal microstructure. Within this structure, the equiaxed \u0026alpha; phase had a diameter of approximately 2\u0026ndash;5 \u0026mu;m (consistent with the EBSD analysis), while the \u0026alpha;/\u0026beta; lamellar structure typically featured layer thicknesses ranging from 100 to 200 nm, as shown in Fig 4. Considering that the \u0026alpha;/\u0026beta; lamellar structure formed as a result of the cooling of the high-temperature stable \u0026beta; phase, during which the diffusion of elements and atoms was incomplete, we proposed that dislocations were primarily concentrated within the \u0026alpha; lamellae. In contrast, the \u0026beta; lamellae, having undergone no significant structural transformation, contained fewer dislocations and lattice distortions.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.2 Mechanical behavior of Ti6Al4V wire\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe mechanical behavior of Ti6Al4V wire was shown in Fig 5. It could be observed that after solution and aging treatment, the axial tensile strength increased from 1060 MPa in the as-drawn state to 1200 MPa, while the axial compressive yield strength (Rpc0.2) increased from 862 MPa to 1020 MPa. By comparison, it was evident that the mechanical properties were significantly improved after the solution and aging treatment.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2.3 Rolling folding behavior and mechanical resistance of Ti6Al4V wire\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThreads were rolled on wire blanks treated under different aging conditions according to a determined rolling scheme. The number of test samples for each group was 5 pieces (3 pieces for tensile testing), and the folding depth was observed using the metallographic method. The thread forming effect after rolling is shown in Fig 6, and the statistical data are presented in Table 3. The rolling folding depth significantly decreased as the aging temperature increased. When the temperature was raised from 540\u0026deg;C to 560\u0026deg;C, the folding depth decreased from 199 \u0026mu;m to 113 \u0026mu;m, representing a reduction of 43%. The number of samples without folding increased from 1 to 4, and the qualification rate was significantly improved. When the aging temperature reached 580\u0026deg;C, the rolling folding depth further decreased to 90 \u0026mu;m, representing only a 20% reduction compared to the folding depth at 560\u0026deg;C. When the aging temperature reached 620\u0026deg;C, the rolling folding issue was completely eliminated, and no folding problems occurred.\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"107%\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 9.18367%;\"\u003e\n \u003cp\u003escheme\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21.4286%;\"\u003e\n \u003cp\u003eaging treatment\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 69.3878%;\"\u003e\n \u003cp\u003eRolling fold situation\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 9.18367%;\"\u003e\n \u003cp\u003e1-1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21.4286%;\"\u003e\n \u003cp\u003e540℃x4h，Ar\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 69.3878%;\"\u003e\n \u003cp\u003e1 piece without folding; 2 pieces guide end folding 199\u0026mu;m; 1 piece folded through tooth type; One tooth top folded 180\u0026mu;m\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 9.18367%;\"\u003e\n \u003cp\u003e1-2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21.4286%;\"\u003e\n \u003cp\u003e560℃x4h，Ar\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 69.3878%;\"\u003e\n \u003cp\u003e1 tooth crest folded 113\u0026mu;m; the other 4 teeth without fold\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 9.18367%;\"\u003e\n \u003cp\u003e1-3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21.4286%;\"\u003e\n \u003cp\u003e580℃x4h，Ar\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 69.3878%;\"\u003e\n \u003cp\u003eOne tooth top fold 90\u0026mu;m; The remaining 4 pieces have no folding\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 9.18367%;\"\u003e\n \u003cp\u003e1-4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 21.4286%;\"\u003e\n \u003cp\u003e620℃x4h，Ar\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 69.3878%;\"\u003e\n \u003cp\u003e5 pieces are not folded\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3 Mechanical properties and rolling folding of titanium alloy bolts under different aging regimes\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAs shown in Fig. 7, the mechanical behavior of the bolt after rolling forming was statistically analyzed. When the aging temperature increased from 540 \u0026deg;C to 580 \u0026deg;C, the tensile strength and shear strength did not change significantly. It was determined that aging in this temperature region had little effect on the performance. With the increase of aging temperature, when the temperature reached more than 620 \u0026deg;C, the mechanical properties decreased significantly, and the tensile properties decreased by nearly 1.5 KN, with a reduction of 6%. It was observed that as the aging temperature increased, the \u0026alpha; phase tended to grow gradually, accompanied by a decrease in strength. A slight reduction in strength helped avoid the phenomenon of rolling wire folding.\u003c/p\u003e"},{"header":"3 Conclusions","content":"\u003cp\u003eThis research investigated the effects of aging treatment on the mechanical behavior and thread rolling folding behavior of Ti6Al4V wire. By analyzing the properties before and after aging, as well as the thread rolling folding behavior post-processing, the following conclusions were obtained:\u003c/p\u003e\n\u003cp\u003e(1) The microstructure of the solution-treated and aged state consisted of equiaxed \u0026alpha; grains uniformly distributed on the \u0026beta; matrix. The grains became finer, and the smaller \u0026alpha; grain size and thinner \u0026alpha;/\u0026beta; lamellar structure contributed to enhancing the alloy\u0026apos;s strength.\u003c/p\u003e\n\u003cp\u003e(2) When the mechanical properties of the wire after solution treatment and aging were compared, it was found that the solution treatment and aging process significantly increased the dislocation density of the \u0026alpha; phase, markedly improving the tensile and compressive properties of the wire.\u003c/p\u003e\n\u003cp\u003e(3) By comparing and analyzing the relationship between mechanical properties, microstructure, and folding behavior at various aging temperatures, it was observed that within the temperature range of 540-580\u0026deg;C, the grain size of the equiaxed \u0026alpha; phase was the primary factor influencing the thread rolling folding behavior. After aging at 620\u0026deg;C, the thread rolling folding behavior was influenced by both the grain size of the equiaxed \u0026alpha; phase and the mechanical properties, but the grain size remained the dominant factor.\u003c/p\u003e\n\u003cp\u003e(4) When higher mechanical properties were required, aging treatment at 560-580\u0026deg;C was recommended. When lower mechanical properties were acceptable, aging at 620\u0026deg;C was preferable, as it resulted in favorable thread morphology and ensured the product\u0026apos;s service performance.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eDate availability\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe data that support the findings of this study are within the Article, or available from the corresponding author upon reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions statement\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eYue Qi: Writing\u0026ndash;original draft, Conceptualization. Shuo Zhao: Investigation, Conceptualization. Yinxiang Chai: Data curation. Dongmei Chen: Data curation. Kun Zhang: Data curation. Hongye Sun: Data curation. Quanshi Cheng: Formal analysis. Wensheng Li: Investigation. Zhongliang Lin: Investigation. Han Zhang: Investigation.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAdditional information\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eOpen Access\u0026nbsp;\u003c/strong\u003eThis article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article\u0026rsquo;s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article\u0026rsquo;s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eRen, Y. et al. Enhancing the energy absorption capacity of Ti\u0026ndash;6Al\u0026ndash;4V lattice structure manufactured by additive manufacturing through β-annealing [J]. Journal of Materials Research and Technology, 35 2369\u0026ndash;2376. 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Technol.\u003c/em\u003e \u003cb\u003e35\u003c/b\u003e, 869\u0026ndash;880. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://doi.org/10.1016/j.jmrt.2025.01.055\u003c/span\u003e\u003cspan address=\"10.1016/j.jmrt.2025.01.055\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e (2025).\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Titanium wires, Aging treatment, Material strength, Rolling-induced folding","lastPublishedDoi":"10.21203/rs.3.rs-6252489/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6252489/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eAs a critical component in the field of aerospace assembly, the mechanical and processing properties of titanium alloy wire are pivotal indicators determining the performance of fasteners. In this research, Ti6Al4V wire, post-drawing, was subjected to solution treatment at 960\u0026thinsp;\u0026plusmn;\u0026thinsp;8\u0026deg;C for 1 hour, followed by aging treatments at 540\u0026deg;C, 560\u0026deg;C, 580\u0026deg;C, and 620\u0026deg;C. The microstructural characteristics and mechanical behavior of the wire post-heat treatment were thoroughly characterized. The findings revealed that the solution and aging treatments significantly enhanced the mechanical properties of the Ti6Al4V wire. Specifically, the tensile yield strength increased from 882 MPa to 1060 MPa, and the average axial compressive performance, Rpc0.2, improved from 859 MPa to 1020 MPa. It was observed that the resistance to thread fold formation, as well as the tensile and shear properties of the bolts, gradually declined with increasing aging temperatures. However, it was also noted that lower shear performance effectively mitigated the occurrence of rolling-induced folding defects during processing. The research demonstrated that an optimized heat treatment regimen can effectively address the issue of rolling-induced folding in titanium alloy wires, thereby enhancing the mechanical performance of fasteners.\u003c/p\u003e","manuscriptTitle":"Research on the influence of aging treatment on the folding behavior and mechanical behavior of rolling silk in titanium alloy wire","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-04-14 17:54:04","doi":"10.21203/rs.3.rs-6252489/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"3682c405-aed6-43da-94c8-06e105654461","owner":[],"postedDate":"April 14th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":46974308,"name":"Physical sciences/Materials science/Materials for devices"},{"id":46974309,"name":"Physical sciences/Materials science/Structural materials"}],"tags":[],"updatedAt":"2025-04-29T10:38:42+00:00","versionOfRecord":[],"versionCreatedAt":"2025-04-14 17:54:04","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6252489","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6252489","identity":"rs-6252489","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}