{"paper_id":"3df1a33d-a545-4f6b-98b3-a97b3b984370","body_text":"Experimental Study on Titanium Alloy Cutting Property and Wear Mechanism with Circular-arc Milling Cutters | 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 Research Article Experimental Study on Titanium Alloy Cutting Property and Wear Mechanism with Circular-arc Milling Cutters Tao Chen, Gang Liu, Jiaqiang Liu, Hui Xiao, Chunhui Li, Xianli Liu This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-1268000/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 28 Apr, 2023 Read the published version in Chinese Journal of Mechanical Engineering → Version 1 posted 5 You are reading this latest preprint version Abstract Titanium alloy has been applied in the field of aerospace manufacturing for its high specific strength and hardness. Nonetheless, these properties also cause general problems in the machining, such as processing inefficiency, serious wear, poor workpiece face quality, etc. Aiming at the above problems, this paper carried out a comparative experimental study on titanium alloy milling based on the CAMC and BEMC. The variation law of cutting force and surface quality of the two tools was obtained, and the wear mechanism was analyzed. The conclusion is that in contrast with BEMC, under the action of cutting thickness thinning mechanism, the force of CAMC was less, and its fluctuation was more stable. The flank wear was uniform and near the cutting edge, and the wear rate was slower. In the early period, the wear mechanism of CAMC was mainly adhesion. Gradually, oxidative wear also occurred with milling. Furthermore, the surface residual height of CAMC was lower. There is no obvious peak and trough accompanied with less surface defects. Circular-arc milling cutter Titanium alloy Ball-end milling cutter Milling force Tool wear Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 1 Introduction Titanium alloy is widely applied to the aerospace industry owing to its high strength and hardness, outstanding high and low temperature performance, etc [1-2]. For example, aircraft engine turbine blades, engine shell and other parts are made of titanium alloy. Yet the titanium alloy is characterized by high chemical reactivity and low elastic modulus [3]. This results in low machining efficiency, severe wear and inferior surface quality in structural parts processing [4-5]. At present, ball-end milling cutter (BEMC) is mostly used for machining titanium alloy structural parts. However, the poor machining quality and low milling efficiency of BEMC milling steep surface structural parts had severely restricted the application and promotion of titanium alloys. Therefore, it is an urgent requirement to conduct study on the development and performance of new structure cutting tools for the future titanium alloy processing industry. In the aspect of cutting performance research and structure design of BEMC, Liang et al. [6] conducted the experiment of milling TC17 with cemented carbide BEMC and found that changing the tool cutting direction was conducive to improve the surface residual stress and tool wear. Cheng et al. [7] optimized the design of BEMC by changing the cutter geometrical parameters, and analyzed the variation laws of the optimized cutter milling force by using the finite element method. Chen et al. [8] proposed a mathematical model of spiral edge curve, which overcame the disadvantage of large calculation in traditional spiral edge modeling approach, and improved the processing efficiency and cutting stability. Zhang et al. [9] combined the bionic structure with BEMC, established a finite element model of biomimetic BEMC machining process, and studied the variation laws of cutting force. Chen et al. [10] conducted a study on new concave-arc BEMC and obtained a higher profile accuracy of the milling cutter by controlling the feed speed of the grinding wheel. Jin et al. [11] designed two kinds of BEMC with special cutting edge, and carried out milling experiments, which proved that these two kinds of tools can obtain higher machining accuracy and smaller main cutting force in finishing. Antoniadis et al. [12] established the surface morphology and roughness forecasting model of BEMC, and verified the validity of the model through experiments. Abbasi et al. [13] analyzed the influence of the inclination angle of the 5-axes BEMC on the machining deformation of thin-walled parts. The results found that near the angle perpendicular to the workpiece surface, the milling speed and milling force of the cutter were low, which helped to improve the machining accuracy. Many scholars have also studied the new tool structure for difficult-to-machine materials. Wang et al. [14] presented a revolving cycloid milling cutter with large spiral angle and front angle. The experiment showed that compared with BEMC, its wear area was shallower and wider, and the processing process produced smaller axial force and tangential force. Song et al. [15] introduced a way to design variable pitch end milling cutter, and obtained the milling speed range under the stable condition of high-speed milling. Yusoff et al. [16] combined the semi discretization method with the difference method and proposed the optimal structure of variable screw cutter and variable pitch cutter. The experimental result showed that the chatter stability of the optimized cutter was improved by 5 times match with ordinary cutter. Li et al. [17] developed a barrel ball milling cutter and offered a method to select cutting parameter and calculate tool position. Krishnaraj et al. [18] conducted a high-speed milling experiment of Ti6Al4V with cemented carbide end milling cutter. The results showed that the cutting depth and feed speed had a significant effect on the milling force, and the milling speed had a significant effect on temperature. Chen et al. [19] conducted a comparative experiment of milling TC11 with self-propelled rotary cutter and indexable cutter. And the conclusions were obtained that the wear mechanism of self-propelled rotary cutter and influence mechanism of wear on processing performance. In summary, related scholars have performed significant researches on the milling of titanium alloys with BEMC and ordinary end milling cutter [20-22]. The researches on titanium alloy special integral milling cutters mostly focuse on the optimization of tool geometric characteristics and multi-axis machining center toolpath planning [23-24]. Machining efficiency and tool life are still important factors affecting titanium alloy processing. Compared with BEMC, circular-arc milling cutter (CAMC) has a larger radius of cutting edge, which can greatly increase the cutting bandwidth. Besides, the CAMC eliminates the influence of cutter body structure size on cutting edge radius, forming a longer effective cutting edge and improving the utilization rate of tool material. For the purpose of further exploring the milling performance of CAMC, a comparative experimental research on titanium alloy milling with BEMC and CAMC was carried out. Combined with milling force, tool wear morphology, chip morphology and machined surface quality, the milling performance of the two kinds of tools were analyzed, which provided theoretical support for the application and popularization of CAMC. 2 Experimental Design The experimental system is shown in Figure 1. The workpiece material was TC4, and its size was 150 mm×100 mm×30 mm. The machine tool used in the experiment was VDL-1000E high-speed milling center. Furthermore, BEMC and CAMC were installed on it. The substrate materials of the two tools were K88UF cemented carbide with WC as the main component and binder Co accounted for 10%. Both of the tools were coated with AlCrN and the coated layer thickness was 4 μm. The radius of BEMC was 5 mm, the side edge rake angle 6°, the flank angle 12°, the helix angle 30°. The radius of CAMC was 5 mm, the end edge radius 9 mm, the side edge radius 45 mm, the rake angle 6°, the flank angle 12°, the helical angle of helical groove 30°. The experimental parameters shown in Table 1 were designed to investigate the impact of machining parameters on the cutting force. Side milling process was conducted in the down milling with BEMC and CAMC respectively. The data of cutting force was collected by Kistler 9139AA dynamometer For fear of the deviation of experimental results due to extreme parameters, the processing parameters were fixed: milling speed 70 m/min, feed per tooth 0.06 mm/z, cutting width 0.3 mm. Each time when the milling distance reached 30 meters, the tools were removed. The SU3500 scanning electron microscope was employed to detect the flank wear morphology of BEMC and CAMC. Then the wear area was analyzed by Bruker xflash630 energy spectrometer. Meanwhile, disboard the workpiece, detect workpiece face quality by the Talysurf CCI white-light interferometer. The surface roughness was characterized by S q , the root mean square deviation of the surface contour height. Table 1 Experimental parameters Serial Number Speed( V c ) (m/min) Feed per tooth( f z ) (mm/z) Width( a e ) (mm) Tools Nos.1-8 50、70、90、110 0.06 0.3 BEMC CAMC Nos.9-14 70 0.04、0.08、0.10 0.3 Nos.15-20 70 0.06 0.1、0.2、0.4 3 Analysis Of Experimental Results 3.1 Analysis of milling forces The forces variation law of two kinds of tools with milling speed, feed per tooth and cutting width was shown in Figure 2. As can be seen from the figure, the forces change trend of the two tools with the milling speed was basically the same, which increased with the milling speed increasing and decreased gradually when the milling speed more than 90 m/min. At the same time, the growth of feed per tooth and cutting width increased the cutting resistance, and the milling forces in all directions of both tools also enlarged significantly. Because of the larger radius side edge, the CAMC narrower cutting region reduced the cutting thickness and the milling force. When the cutting volume enlarged, the effect of reducing the milling force was more outstanding. The forces of CAMC were less than that of BEMC, especially the tangential force F x was about 15% smaller than that of BEMC, while the axial force F z of CAMC was not significantly lower than that of BEMC. The F z of CAMC was only 3% lower than that of BEMC with feed per tooth 0.10 mm/z. The reason is that the different helix angles in the cutting area of tools can result in different force decomposition effects. Thus led to the different proportion of the forces in all directions between BEMC and CAMC. Figure 3 shows the actual measured data of tangential force F x of the two kinds of tools at milling speed of 70 m/min, feed per tooth of 0.06 mm/z and cutting width of 0.3 mm. It can be seen that the F x peak value of BEMC was higher than that of CAMC, and the former F x peak value fluctuation range was also greater than that of the latter. This can be interpreted as CAMC relieved the fluctuation of the cutting force caused by the frictional resistance and mechanical shock concentration for its flat cutting edge. Thus the processing stability was higher. 3.2 Analysis of tool wear process Figure 4 shows the flank wear morphology in different milling lengths. It is observed that the adhesive layer appeared on the flank of BEMC and CAMC obviously at milling length 60 m. Since the strong affinity of titanium alloy, cutting area of flank face formed bonding under friction. But the difference is that the bonding of BEMC was relatively concentrated and blocky, while the flank adhesive layer of CAMC was more uniform. Moreover, its width was smaller than that of BEMC and appeared as a strip. As the milling progressed, the extrusion and friction between the tool and the workpiece intensified, which led to a degradation of cutting performance. When the machining length reached 150m, the bonding on the cutting edge of BEMC fell off constantly, which weakened the cohesion between the coating and substrate. Furthermore, because of the large curvature transformation of the cutting edge, the force on both sides and the middle of the cutting edge was uneven. Therefore, under the action of mechanical and thermal shock, micro notches occurred at the weak part. At this period, flank adhesive layer of CAMC also fell off continuously, forming a strip-shaped wear belt with intermittent coating. However, the flatter cutting edge of CAMC made the contact between the flank face and the machined surface more uniform, and thereby avoided tool tipping. As the milling length reached 240 m, the gradually increasing stress on the cutting edge of BEMC accelerated the separation of substrate material particles, and there was tool tipping on the cutting edge. Although tiny tipping also appeared on CAMC, they were smaller and more dispersed than those of BEMC, and the cutting edge remained relatively intact. 3.3 Analysis of tool wear mechanism Figure 5(a) and, Figure, (b) shows the fl, nk wear morphology of BEMC and CAMC at the machining length 60m. It can be seen that the two kinds of tools had different degrees of bonding. Due to the concentration of cutting area, under high stress and high temperature, there was a large bonding on the flank of BEMC. The wear area was not uniform, and some coating was removed nearby. At this point, block bonding appeared at the cutting edge of CAMC. And strip adhesive layer appeared at the bottom of block bonding, which was evenly coated on the tool surface. Compared with BEMC, CAMC had smaller block bonding and narrower tool wear area. When the machining length reached 150m, the bonding at the cutting edge of BEMC increases, and a large area of coating peeling occurred, exposing the tool substrate (Figure 5(c)). O and Ti were found by the analysis of the material composition. It can be speculated that the temperature rise in this region accelerated the diffusion of Ti to the tool substrate while the oxidation wear occurred. Meanwhile, the bonding debris on CAMC continuously peeled off and took away the coating, and the wear area presented a uniform strip shape (Figure 5(d)). Furthermore, large amount of Al, N and Cr were detected in the wear area, which indicated that the coating was not completely peeled off and in a slow grinding process. It can be deduced that CAMC was in a stable wear period. Additionally, a small amount of O was found in the cutting area, and thus CAMC also had slight oxidation wear. Figure 5(e) and Figure 5(f) shows the flank wear morphology of two tools at the machining length 240m. There was tipping at the cutting edge of BEMC, and a tight adhesive layer was found in these areas. It indicated that tool tipping had occurred at an earlier time. Further elemental analysis results of the wear area shows that the content of C increases and the content of Co decreases at the cutting edge. At this time, the diffusion of Co to the inside led to lack on the surface, resulting in a decrease in the bonding strength between the substrate C particles. So the substrate material fell off together with the bonding, which was the main reason for the formation of severe tool tipping. In this period, the coating peeling of CAMC intensified, and the width of the wear area increased. Additionally, there was a small amount of adhesive layer and tiny notches occurred at the same time. However, since the flank face of CAMC contacted the workpiece more evenly, the heat dissipation conditions were improved while reducing friction. Therefore, the spalling of tool substrate was avoided. The energy spectrum analysis showed that the content of O increased and there was a small amount of Ti at the tipping area. This showed that oxidative wear and slight diffusion wear occurred at the same time. 3.4 Effect of tool wear on surface quality Figure 6(a) and Figure 6(b) shows comparison of the machined surface morphology at the machining length 60 m. It can be observed that outstanding peak and trough appeared on the surface machined by BEMC, and the S q was 0.679 µm. Due to the small radius of the ball head, BEMC cut into the workpiece and produced obvious ball pits in the wave trough. In contrast with BEMC, CAMC had a flatter machining surface, with only shallow strip grooves and slight wave crests. Its S q was 0.467 µm and smaller than that of BEMC. When the machining length was 150 m, the two kinds of tools entered into a stable wear stage. At this point, the wear of BEMC was relatively severe. The peak and trough of the machined surface were more remarkable, and reflected in the wave peak height increasing. The maximum height of the peak top S p was 3.713 µm. Concurrently the defects at the cutting edge were reflected on the machining surface, and there were bulges along the feed direction at the trough floor (Figure 6(c)). The wave peak on the machining surface of CAMC had also begun to become prominent, and narrow trough had appeared. Compared with BEMC, its surface quality had not significantly decreased. The S q was 0.565 µm, which was much smaller than 0.905 µm of BEMC (Figure 6(d)). As the machining length increased, continuous abrasion and mechanical shock between BEMC and the workpiece led to tool tipping and intensified the squeeze plowing action. Therefore, when the machining length was 240 m, the bulge on the surface was more outstanding, and the ball pit in the wave trough became irregular and more rugged. The peak height increased further, and the S q reached 1.087 µm (Figure 6(e)). The surface quality machined by CAMC also dropped to some degree. The uniform wave peak disappeared and was replaced by irregular wave peak and shallow trough. These phenomena were caused by the notches of CAMC and the decrease of machining stability. By contrast, the S q value of CAMC was only 0.678 µm, so the surface quality was better (Figure 6(f)). 3.5 Analysis and discussion According to the above, the residual height value of CAMC was lower, and the surface quality was better. This paper analyzed the actual processing situation of BEMC and CAMC, and established the mathematical model of residual height. Figure 7 shows the comparison of machined surface residual height after milling by BEMC and CAMC. The residual height of machined surface h is: (1) In the expressions R is the radius of the cutting edge, L the processing line spacing. As can be seen from Figure 7, under the condition of the same processing line spacing and milling width, the larger radius cutting edge of CAMC cut into the workpiece, resulting in more uniform thickness and thinner average cutting thickness. Moreover, it can be seen from Exps. (1) that the surface residual height h at the two adjacent tool paths overlap of CAMC is lower under the condition of fixed processing row spacing L . Thus the surface quality is improved. To investigate the milling forces of the two kinds of tools, it is indispensable to create the milling force model diagram in the normal plane reference frame based on the actual cutting process (Figure 8). The cutting area is equivalent to point A . At point A , the cutting edge receives a feed force F c perpendicular to the base plane P r and a tangential force F t directed to the cutting edge center in the normal section P n . The resultant shear force F of these two forces can be expressed as follows. \\(F=\\frac{{{\\tau _s} \\cdot {a_e} \\cdot {H_D}}}{{\\sin \\phi \\cdot \\cos (\\phi +\\eta - \\gamma ')}}\\) (2) In the expressions τ s stands for the shear stress, a e the cutting width, H D the instantaneous undeformed cutting thickness, φ the shear angle, γ ' working rake angle, η the friction angle determined by the experiment. Taking into account the differences in cutting performance caused by different cutting areas of the tool, it is necessary to probe the impact of the geometric characteristics on helix angle β . The cutting area of CAMC is the side edge, and its helix angle is 30°. The cutting area of BEMC is the end edge, both its equivalent helix angle β ' and working rake angle γ ' measured in main section P n vary with the axial position angle θ of point A , as is shown in the following expression. \\(\\beta '=\\arccos \\left( {\\frac{{\\cot \\beta }}{{\\sqrt {{{(\\sin \\theta )}^4}+{{\\left( {\\cot \\beta } \\right)}^2}} }}} \\right)\\) (3) \\(\\gamma '=sin\\gamma {\\cos ^2}\\beta '{\\text{+}}{\\sin ^2}\\beta '\\) (4) According to Exps. (3), the end edge equivalent helix angle of BEMC increases nonlinearly with the axial position angle θ and is less than the helix angle of CAMC by 30°. Compared with BEMC, constant helix angle of the side edge of CAMC makes the cutting process more stable. Moreover, the larger helix angle can effectively decompose the main cutting force into axial direction, which makes the axial force component increase significantly. This is the reason that the decline of F x and F y of CAMC is more remarkable than that of F z (Figure 8). Exps. (4) demonstrates that the working rake angle γ ' of CAMC is larger, which will be mentioned in the calculation of the cutting force later. The other parameters in Exps (2) can be expressed as: \\({H_D}_{{\\hbox{max} }}=\\frac{{\\sqrt {4{R^2} - {a_e}^{2}} }}{{2\\sin \\left[ {\\arctan (\\frac{{\\sqrt {4{R^2} - {a_e}^{2}} }}{{{a_e} - 2{f_z}}})} \\right]}}\\) (5) \\(\\phi {\\text{=}}\\frac{\\pi }{4} - \\frac{{\\eta - \\gamma '}}{2}\\) (6) Therefore, the maximum shearing force F max of a single cutting edge in the cutting process can be obtained. \\({F_{\\hbox{max} }}=\\frac{{{\\tau _s} \\cdot {a_e} \\cdot \\sqrt {4{R^2} - {a_e}^{2}} }}{{2\\sin \\left[ {\\arctan (\\frac{{\\sqrt {4{R^2} - {a_e}^{2}} }}{{{a_e} - 2{f_z}}})} \\right] \\cdot \\sin (\\frac{\\pi }{4} - \\frac{{\\eta - \\gamma '}}{2}) \\cdot \\cos (\\frac{\\pi }{4}+\\frac{{\\eta - \\gamma '}}{2})}}\\) (7) It can be seen from Exps. (5) that CAMC reduces the maximum instantaneous cutting thickness H Dmax for its larger side edge radius R . Therefore, the conclusion can be drawn from Exps. (7) that the large working rake angle of CAMC and the cutting thickness thinning mechanism reduce the maximum cutting force during the cutting process jointly. Furthermore, the tool wear was effectively relieved. It is worth noting that the larger radius and flatter cutting edge of CAMC make the wear area dispersed and uniform to avoid heat concentration. Consequently, this also has a positive effect on prolonging tool life. 4 Conclusions In this paper, the cutting property comparison study of ball-end milling cutters (BEMC) and circular-arc milling cutters (CAMC) was carried out. The comparative analysis was made of milling forces, tool wear and surface quality. The following conclusions were obtained. (1) In contrast with BEMC, the tangential force and radial force decreased obviously under the action of cutting thickness thinning mechanism. In addition, the tangential force fluctuation amplitude of CAMC was significantly smaller than that of BEMC, which represented excellent dynamic processing performance. (2) The flank face of CAMC was dominated by adhesive wear, and the wear area was near the cutting edge and narrower. After a long cutting time, obvious oxidation wear was observed. The width and depth of the wear area increased slowly. The final failure occurred with the appearance of the notches. (3) In the whole cutting process, CAMC had better surface quality. There was no obvious peak and trough in machined surface, and the surface roughness S q was kept at a low level. (4) The machined surface produced by CAMC had lower residual height under the action of large cutting edge radius. Compared with BEMC, the large working rake angle of CAMC and the reduction of cutting thickness decreased the maximum cutting force. And the flatter cutting edge makes the heat even, effectively relieving tool wear. Declarations Acknowledgements Not applicable Funding Supported by National Natural Science Foundation of China (Grant No. 51975168). Availability of data and materials All data generated or analysed during this study are included in this published article. Authors’ contributions The author’ contributions are as follows: Tao Chen, has organized the project, designed the experiments, and written the manuscript; Gang Liu, has designed the experiments, analyzed and arranged data, and written the manuscript; Jia-Qiang Liu, has conducted the experiments, and collected and analyzed data; Hui Xiao, has conducted the experiments, and collected and analyzed data; Chun-Hui Li, has reviewed the manuscript; Xian-Li Liu, has reviewed the manuscript. 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Cite Share Download PDF Status: Published Journal Publication published 28 Apr, 2023 Read the published version in Chinese Journal of Mechanical Engineering → Version 1 posted Reviews received at journal 19 Mar, 2022 Reviewers invited by journal 17 Mar, 2022 Editor invited by journal 25 Feb, 2022 Editor assigned by journal 18 Jan, 2022 First submitted to journal 16 Jan, 2022 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. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-1268000\",\"acceptedTermsAndConditions\":true,\"allowDirectSubmit\":false,\"archivedVersions\":[],\"articleType\":\"Research Article\",\"associatedPublications\":[],\"authors\":[{\"id\":91548851,\"identity\":\"853f3ba8-2474-408c-b583-fe7718c80a9a\",\"order_by\":0,\"name\":\"Tao Chen\",\"email\":\"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA4klEQVRIiWNgGAWjYDACCQglZ8DAAxU5QIwWoCJjiJYEErQkbiBaC//s5mOPP9TYpG+XPntM8ucPBjm+GwmMnwvwWXLnWLrBgWNpuTv78tKkeRIYjCVvJDBLz8CjxUAix0ziANvh3A1neMykgQ5L3HAjgY2ZB6+W/G8SB/4dTjcAapH8kcBQT4SWHDaJg22HE0BaJIAOSzAgpEXiRpqZxNm+NMMNZ/iSrXnSJAxnnnnYLI1PC/+M5GcSFd9s5A3O8B68+cPGRp7vePLBz/i0YNgKxIwNJGgYBaNgFIyCUYANAABbAUmQEonH4gAAAABJRU5ErkJggg==\",\"orcid\":\"\",\"institution\":\"Harbin University of Science and Technology\",\"correspondingAuthor\":true,\"prefix\":\"\",\"firstName\":\"Tao\",\"middleName\":\"\",\"lastName\":\"Chen\",\"suffix\":\"\"},{\"id\":91548852,\"identity\":\"dbb2ef4f-4b79-4943-b119-07946385df45\",\"order_by\":1,\"name\":\"Gang Liu\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Harbin University of Science and Technology\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Gang\",\"middleName\":\"\",\"lastName\":\"Liu\",\"suffix\":\"\"},{\"id\":91548853,\"identity\":\"b8b6c99c-ff34-456b-8afd-ec5d791a3ea9\",\"order_by\":2,\"name\":\"Jiaqiang Liu\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Harbin University of Science and Technology\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Jiaqiang\",\"middleName\":\"\",\"lastName\":\"Liu\",\"suffix\":\"\"},{\"id\":91548854,\"identity\":\"24bd1760-123b-49a2-8910-e9d1737bc9bf\",\"order_by\":3,\"name\":\"Hui Xiao\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Harbin University of Science and Technology\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Hui\",\"middleName\":\"\",\"lastName\":\"Xiao\",\"suffix\":\"\"},{\"id\":91548855,\"identity\":\"719bb26d-6d2f-47a1-91ca-7fdecc246c57\",\"order_by\":4,\"name\":\"Chunhui Li\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Harbin University of Science and Technology\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Chunhui\",\"middleName\":\"\",\"lastName\":\"Li\",\"suffix\":\"\"},{\"id\":91548856,\"identity\":\"d8d6a0a0-adba-4e62-843d-f2ad5e7bf3c1\",\"order_by\":5,\"name\":\"Xianli Liu\",\"email\":\"\",\"orcid\":\"\",\"institution\":\"Harbin University of Science and Technology\",\"correspondingAuthor\":false,\"prefix\":\"\",\"firstName\":\"Xianli\",\"middleName\":\"\",\"lastName\":\"Liu\",\"suffix\":\"\"}],\"badges\":[],\"createdAt\":\"2022-01-17 09:23:04\",\"currentVersionCode\":1,\"declarations\":\"\",\"doi\":\"10.21203/rs.3.rs-1268000/v1\",\"doiUrl\":\"https://doi.org/10.21203/rs.3.rs-1268000/v1\",\"draftVersion\":[],\"editorialEvents\":[{\"content\":\"https://doi.org/10.1186/s10033-023-00887-5\",\"type\":\"published\",\"date\":\"2023-04-28T20:38:35+00:00\"}],\"editorialNote\":\"\",\"failedWorkflow\":false,\"files\":[{\"id\":19481492,\"identity\":\"b33ad3fa-d00c-4e61-8536-8386648e22f2\",\"added_by\":\"auto\",\"created_at\":\"2022-03-22 14:31:47\",\"extension\":\"png\",\"order_by\":1,\"title\":\"Figure 1\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":456753,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eExperimental system\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"fig1.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-1268000/v1/3609a9292a673075d3c8661c.png\"},{\"id\":19481495,\"identity\":\"e24df4d7-85de-40c1-b30a-5a1bb068db2a\",\"added_by\":\"auto\",\"created_at\":\"2022-03-22 14:31:47\",\"extension\":\"png\",\"order_by\":2,\"title\":\"Figure 2\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":311952,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eVariation law of cutting force with milling parameters: \\u003cstrong\\u003ea\\u003c/strong\\u003e Milling speed, \\u003cstrong\\u003eb\\u003c/strong\\u003e Feed per tooth and \\u003cstrong\\u003ec\\u003c/strong\\u003e Cutting width\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"fig2.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-1268000/v1/99cada8931d09ed6bccf435e.png\"},{\"id\":19481506,\"identity\":\"01747c91-ec78-401f-b423-127d9f16609a\",\"added_by\":\"auto\",\"created_at\":\"2022-03-22 14:34:47\",\"extension\":\"png\",\"order_by\":3,\"title\":\"Figure 3\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":124874,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eActual measured data of tangential force \\u003cem\\u003eF\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003ex\\u003c/em\\u003e\\u003c/sub\\u003e.\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"fig3.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-1268000/v1/b5ff719c5e24995e0430b3a2.png\"},{\"id\":19481763,\"identity\":\"1f120ec2-9fe6-48b5-ac4d-a844dfe03712\",\"added_by\":\"auto\",\"created_at\":\"2022-03-22 14:37:47\",\"extension\":\"png\",\"order_by\":4,\"title\":\"Figure 4\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":507432,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eFlank Wear morphology\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"fig4.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-1268000/v1/829df21d5ee536072b00e5f6.png\"},{\"id\":19481508,\"identity\":\"2e4aa671-54b7-4053-9131-5e25a3eee037\",\"added_by\":\"auto\",\"created_at\":\"2022-03-22 14:34:48\",\"extension\":\"png\",\"order_by\":5,\"title\":\"Figure 5\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":1046814,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eFlank wear morphology at different length\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"fig5.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-1268000/v1/0de291382389ce82b180b120.png\"},{\"id\":19481493,\"identity\":\"a362f737-e4b5-400c-96f1-c6608de5cea5\",\"added_by\":\"auto\",\"created_at\":\"2022-03-22 14:31:47\",\"extension\":\"png\",\"order_by\":6,\"title\":\"Figure 6\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":1137941,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eComparison of the machined surface morphology at different length\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"fig6.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-1268000/v1/6b0f1b9e347197148b91ab33.png\"},{\"id\":19481497,\"identity\":\"a9601991-a14b-4d18-9752-55c0eaff74f7\",\"added_by\":\"auto\",\"created_at\":\"2022-03-22 14:31:47\",\"extension\":\"png\",\"order_by\":7,\"title\":\"Figure 7\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":151302,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eComparison of machined surface residual height: \\u003cstrong\\u003ea\\u003c/strong\\u003e BEMC and \\u003cstrong\\u003eb\\u003c/strong\\u003e CAMC\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"fig7.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-1268000/v1/93f674bdd19b179228d88cb0.png\"},{\"id\":19481499,\"identity\":\"09f44505-15c4-4359-a3c9-a6c9b9d409a8\",\"added_by\":\"auto\",\"created_at\":\"2022-03-22 14:31:48\",\"extension\":\"png\",\"order_by\":8,\"title\":\"Figure 8\",\"display\":\"\",\"copyAsset\":false,\"role\":\"figure\",\"size\":137723,\"visible\":true,\"origin\":\"\",\"legend\":\"\\u003cp\\u003eMilling force model diagram: \\u003cstrong\\u003ea\\u003c/strong\\u003e BEMC and \\u003cstrong\\u003eb\\u003c/strong\\u003e CAMC\\u003c/p\\u003e\",\"description\":\"\",\"filename\":\"fig8.png\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-1268000/v1/81b5a54d6d08402911f563aa.png\"},{\"id\":44728161,\"identity\":\"8dbdabb5-5103-4deb-ad8e-eb2e14c05c2c\",\"added_by\":\"auto\",\"created_at\":\"2023-10-16 21:01:29\",\"extension\":\"pdf\",\"order_by\":0,\"title\":\"\",\"display\":\"\",\"copyAsset\":false,\"role\":\"manuscript-pdf\",\"size\":4010574,\"visible\":true,\"origin\":\"\",\"legend\":\"\",\"description\":\"\",\"filename\":\"manuscript.pdf\",\"url\":\"https://assets-eu.researchsquare.com/files/rs-1268000/v1/f469ce6a-540c-4af1-b903-e8ffb3ea8e16.pdf\"}],\"financialInterests\":\"\",\"formattedTitle\":\"Experimental Study on Titanium Alloy Cutting Property and Wear Mechanism with Circular-arc Milling Cutters\",\"fulltext\":[{\"header\":\"1 Introduction\",\"content\":\"\\u003cp\\u003eTitanium alloy is widely applied to the aerospace industry owing to its high strength and hardness, outstanding high and low temperature performance, etc [1-2]. For example, aircraft engine turbine blades, engine shell and other parts are made of titanium alloy. Yet the titanium alloy is characterized by high chemical reactivity and low elastic modulus [3]. This results in low machining efficiency, severe wear and inferior surface quality in structural parts processing [4-5]. At present, ball-end milling cutter (BEMC) is mostly used for machining titanium alloy structural parts. However, the poor machining quality and low milling efficiency of BEMC milling steep surface structural parts had severely restricted the application and promotion of titanium alloys. Therefore, it is an urgent requirement to conduct study on the development and performance of new structure cutting tools for the future titanium alloy processing industry.\\u003c/p\\u003e\\n\\u003cp\\u003eIn the aspect of cutting performance research and structure design of BEMC, Liang et al. [6] conducted the experiment of milling TC17 with cemented carbide BEMC and found that changing the tool cutting direction was conducive to improve the surface residual stress and tool wear. Cheng et al. [7] optimized the design of BEMC by changing the cutter geometrical parameters, and analyzed the variation laws of the optimized cutter milling force by using the finite element method. Chen et al. [8] proposed a mathematical model of spiral edge curve, which overcame the disadvantage of large calculation in traditional spiral edge modeling approach, and improved the processing efficiency and cutting stability. Zhang et al. [9] combined the bionic structure with BEMC, established a finite element model of biomimetic BEMC machining process, and studied the variation laws of cutting force. Chen et al. [10] conducted a study on new concave-arc BEMC and obtained a higher profile accuracy of the milling cutter by controlling the feed speed of the grinding wheel. Jin et al. [11] designed two kinds of BEMC with special cutting edge, and carried out milling experiments, which proved that these two kinds of tools can obtain higher machining accuracy and smaller main cutting force in finishing. Antoniadis et al. [12] established the surface morphology and roughness forecasting model of BEMC, and verified the validity of the model through experiments. Abbasi et al. [13] analyzed the influence of the inclination angle of the 5-axes BEMC on the machining deformation of thin-walled parts. The results found that near the angle perpendicular to the workpiece surface, the milling speed and milling force of the cutter were low, which helped to improve the machining accuracy.\\u003c/p\\u003e\\n\\u003cp\\u003eMany scholars have also studied the new tool structure for difficult-to-machine materials. Wang et al. [14] presented a revolving cycloid milling cutter with large spiral angle and front angle. The experiment showed that compared with BEMC, its wear area was shallower and wider, and the processing process produced smaller axial force and tangential force. Song et al. [15] introduced a way to design variable pitch end milling cutter, and obtained the milling speed range under the stable condition of high-speed milling. Yusoff et al. [16] combined the semi discretization method with the difference method and proposed the optimal structure of variable screw cutter and variable pitch cutter. The experimental result showed that the chatter stability of the optimized cutter was improved by 5 times match with ordinary cutter. Li et al. [17] developed a barrel ball milling cutter and offered a method to select cutting parameter and calculate tool position. Krishnaraj et al. [18] conducted a high-speed milling experiment of Ti6Al4V with cemented carbide end milling cutter. The results showed that the cutting depth and feed speed had a significant effect on the milling force, and the milling speed had a significant effect on temperature. Chen et al. [19] conducted a comparative experiment of milling TC11 with self-propelled rotary cutter and indexable cutter. And the conclusions were obtained that the wear mechanism of self-propelled rotary cutter and influence mechanism of wear on processing performance.\\u003c/p\\u003e\\n\\u003cp\\u003eIn summary, related scholars have performed significant researches on the milling of titanium alloys with BEMC and ordinary end milling cutter [20-22]. The researches on titanium alloy special integral milling cutters mostly focuse on the optimization of tool geometric characteristics and multi-axis machining center toolpath planning [23-24]. Machining efficiency and tool life are still important factors affecting titanium alloy processing. Compared with BEMC, circular-arc milling cutter (CAMC) has a larger radius of cutting edge, which can greatly increase the cutting bandwidth. Besides, the CAMC eliminates the influence of cutter body structure size on cutting edge radius, forming a longer effective cutting edge and improving the utilization rate of tool material. For the purpose of further exploring the milling performance of CAMC, a comparative experimental research on titanium alloy milling with BEMC and CAMC was carried out. Combined with milling force, tool wear morphology, chip morphology and machined surface quality, the milling performance of the two kinds of tools were analyzed, which provided theoretical support for the application and popularization of CAMC.\\u003c/p\\u003e\"},{\"header\":\"2 Experimental Design\",\"content\":\"\\u003cp\\u003eThe experimental system is shown in Figure 1. The workpiece material was TC4, and its size was 150 mm\\u0026times;100 mm\\u0026times;30 mm. The machine tool used in the experiment was VDL-1000E high-speed milling center. Furthermore, BEMC and CAMC were installed on it. The substrate materials of the two tools were K88UF cemented carbide with WC as the main component and binder Co accounted for 10%. Both of the tools were coated with AlCrN and the coated layer thickness was 4 \\u0026mu;m. The radius of BEMC was 5 mm, the side edge rake angle 6\\u0026deg;, the flank angle 12\\u0026deg;, the helix angle 30\\u0026deg;. The radius of CAMC was 5 mm, the end edge radius 9 mm, the side edge radius 45 mm, the rake angle 6\\u0026deg;, the flank angle 12\\u0026deg;, the helical angle of helical groove 30\\u0026deg;.\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003eThe experimental parameters shown in Table 1 were designed to investigate the impact of machining parameters on the cutting force. Side milling process was conducted in the down milling with BEMC and CAMC respectively. The data of cutting force was collected by Kistler 9139AA dynamometer\\u003c/p\\u003e\\n\\u003cp\\u003eFor fear of the deviation of experimental results due to extreme parameters, the processing parameters were fixed: milling speed 70 m/min, feed per tooth 0.06 mm/z, cutting width 0.3 mm. Each time when the milling distance reached 30 meters, the tools were removed. The SU3500 scanning electron microscope was employed to detect the flank wear morphology of BEMC and CAMC. Then the wear area was analyzed by Bruker xflash630 energy spectrometer. Meanwhile, disboard the workpiece, detect workpiece face quality by the Talysurf CCI white-light interferometer. The surface roughness was characterized by \\u003cem\\u003eS\\u003csub\\u003eq\\u003c/sub\\u003e\\u003c/em\\u003e, the root mean square deviation of the surface contour height.\\u003c/p\\u003e\\n\\u003cp\\u003eTable 1 \\u0026nbsp;Experimental parameters\\u003c/p\\u003e\\n \\u003ctable border=\\\"0\\\" cellpadding=\\\"0\\\" cellspacing=\\\"0\\\" width=\\\"0\\\"\\u003e\\n \\u003ctbody\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"12.926391382405745%\\\"\\u003e\\n \\u003cp\\u003eSerial Number\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"24.416517055655298%\\\"\\u003e\\n \\u003cp\\u003eSpeed(\\u003cem\\u003eV\\u003csub\\u003ec\\u003c/sub\\u003e\\u003c/em\\u003e)\\u003c/p\\u003e\\n \\u003cp\\u003e(m/min)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"23.6983842010772%\\\"\\u003e\\n \\u003cp\\u003eFeed per tooth(\\u003cem\\u003ef\\u003csub\\u003ez\\u003c/sub\\u003e\\u003c/em\\u003e)\\u003c/p\\u003e\\n \\u003cp\\u003e(mm/z)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"25.493716337522443%\\\"\\u003e\\n \\u003cp\\u003eWidth(\\u003cem\\u003ea\\u003csub\\u003ee\\u003c/sub\\u003e\\u003c/em\\u003e)\\u003c/p\\u003e\\n \\u003cp\\u003e(mm)\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"13.464991023339318%\\\"\\u003e\\n \\u003cp\\u003eTools\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"12.926391382405745%\\\"\\u003e\\n \\u003cp\\u003eNos.1-8\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"24.416517055655298%\\\"\\u003e\\n \\u003cp\\u003e50、70、90、110\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"23.6983842010772%\\\"\\u003e\\n \\u003cp\\u003e0.06\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"25.493716337522443%\\\"\\u003e\\n \\u003cp\\u003e0.3\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd rowspan=\\\"3\\\" width=\\\"13.464991023339318%\\\"\\u003e\\n \\u003cp\\u003eBEMC CAMC\\u003c/p\\u003e\\n \\u003cp\\u003e\\u0026nbsp;\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"14.937759336099585%\\\"\\u003e\\n \\u003cp\\u003eNos.9-14\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"28.21576763485477%\\\"\\u003e\\n \\u003cp\\u003e70\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"27.38589211618257%\\\"\\u003e\\n \\u003cp\\u003e0.04、0.08、0.10\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"29.46058091286307%\\\"\\u003e\\n \\u003cp\\u003e0.3\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003ctr\\u003e\\n \\u003ctd width=\\\"14.937759336099585%\\\"\\u003e\\n \\u003cp\\u003eNos.15-20\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"28.21576763485477%\\\"\\u003e\\n \\u003cp\\u003e70\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"27.38589211618257%\\\"\\u003e\\n \\u003cp\\u003e0.06\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003ctd width=\\\"29.46058091286307%\\\"\\u003e\\n \\u003cp\\u003e0.1、0.2、0.4\\u003c/p\\u003e\\n \\u003c/td\\u003e\\n \\u003c/tr\\u003e\\n \\u003c/tbody\\u003e\\n \\u003c/table\\u003e\"},{\"header\":\"3 Analysis Of Experimental Results\",\"content\":\"\\u003ch3\\u003e3.1 \\u0026nbsp;Analysis of milling forces\\u003c/h3\\u003e\\n\\u003cp\\u003eThe forces variation law of two kinds of tools with milling speed, feed per tooth and cutting width was shown in Figure 2. As can be seen from the figure, the forces change trend of the two tools with the milling speed was basically the same, which increased with the milling speed increasing and decreased gradually when the milling speed more than 90 m/min. At the same time, the growth of feed per tooth and cutting width increased the cutting resistance, and the milling forces in all directions of both tools also enlarged significantly. Because of the larger radius side edge, the CAMC narrower cutting region reduced the cutting thickness and the milling force. When the cutting volume enlarged, the effect of reducing the milling force was more outstanding. The forces of CAMC were less than that of BEMC, especially the tangential force \\u003cem\\u003eF\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003ex\\u003c/em\\u003e\\u003c/sub\\u003e was about 15% smaller than that of BEMC, while the axial force \\u003cem\\u003eF\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003ez\\u003c/em\\u003e\\u003c/sub\\u003e of CAMC was not significantly lower than that of BEMC. The \\u003cem\\u003eF\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003ez\\u003c/em\\u003e\\u003c/sub\\u003e of CAMC was only 3% lower than that of BEMC with feed per tooth 0.10 mm/z. The reason is that the different helix angles in the cutting area of tools can result in different force decomposition effects. Thus led to the different proportion of the forces in all directions between BEMC and CAMC.\\u003c/p\\u003e\\n\\u003cp\\u003eFigure 3 shows the actual measured data of tangential force \\u003cem\\u003eF\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003ex\\u003c/em\\u003e\\u003c/sub\\u003e of the two kinds of tools at milling speed of 70 m/min, feed per tooth of 0.06 mm/z and cutting width of 0.3 mm. It can be seen that the \\u003cem\\u003eF\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003ex\\u003c/em\\u003e\\u003c/sub\\u003e peak value of BEMC was higher than that of CAMC, and the former \\u003cem\\u003eF\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003ex\\u003c/em\\u003e\\u003c/sub\\u003e peak value fluctuation range was also greater than that of the latter. This can be interpreted as CAMC relieved the fluctuation of the cutting force caused by the frictional resistance and mechanical shock concentration for its flat cutting edge. Thus the processing stability was higher.\\u003c/p\\u003e\\n\\u003cdiv class=\\\"Section2\\\" id=\\\"Sec2\\\"\\u003e\\n \\u003ch2\\u003e3.2 Analysis of tool wear process\\u003c/h2\\u003e\\n \\u003cp\\u003eFigure 4 shows the flank wear morphology in different milling lengths. It is observed that the adhesive layer appeared on the flank of BEMC and CAMC obviously at milling length 60 m. Since the strong affinity of titanium alloy, cutting area of flank face formed bonding under friction. But the difference is that the bonding of BEMC was relatively concentrated and blocky, while the flank adhesive layer of CAMC was more uniform. Moreover, its width was smaller than that of BEMC and appeared as a strip.\\u003c/p\\u003e\\n \\u003cp\\u003eAs the milling progressed, the extrusion and friction between the tool and the workpiece intensified, which led to a degradation of cutting performance. When the machining length reached 150m, the bonding on the cutting edge of BEMC fell off constantly, which weakened the cohesion between the coating and substrate. Furthermore, because of the large curvature transformation of the cutting edge, the force on both sides and the middle of the cutting edge was uneven. Therefore, under the action of mechanical and thermal shock, micro notches occurred at the weak part. At this period, flank adhesive layer of CAMC also fell off continuously, forming a strip-shaped wear belt with intermittent coating. However, the flatter cutting edge of CAMC made the contact between the flank face and the machined surface more uniform, and thereby avoided tool tipping. As the milling length reached 240 m, the gradually increasing stress on the cutting edge of BEMC accelerated the separation of substrate material particles, and there was tool tipping on the cutting edge. Although tiny tipping also appeared on CAMC, they were smaller and more dispersed than those of BEMC, and the cutting edge remained relatively intact.\\u003c/p\\u003e\\n\\u003c/div\\u003e\\n\\u003cdiv class=\\\"Section2\\\" id=\\\"Sec3\\\"\\u003e\\n \\u003ch2\\u003e3.3 Analysis of tool wear mechanism\\u003c/h2\\u003e\\n \\u003cp\\u003eFigure 5(a) and, Figure, (b) shows the fl, nk wear morphology of BEMC and CAMC at the machining length 60m. It can be seen that the two kinds of tools had different degrees of bonding. Due to the concentration of cutting area, under high stress and high temperature, there was a large bonding on the flank of BEMC. The wear area was not uniform, and some coating was removed nearby. At this point, block bonding appeared at the cutting edge of CAMC. And strip adhesive layer appeared at the bottom of block bonding, which was evenly coated on the tool surface. Compared with BEMC, CAMC had smaller block bonding and narrower tool wear area.\\u003c/p\\u003e\\n \\u003cp\\u003eWhen the machining length reached 150m, the bonding at the cutting edge of BEMC increases, and a large area of coating peeling occurred, exposing the tool substrate (Figure 5(c)). O and Ti were found by the analysis of the material composition. It can be speculated that the temperature rise in this region accelerated the diffusion of Ti to the tool substrate while the oxidation wear occurred. Meanwhile, the bonding debris on CAMC continuously peeled off and took away the coating, and the wear area presented a uniform strip shape (Figure 5(d)). Furthermore, large amount of Al, N and Cr were detected in the wear area, which indicated that the coating was not completely peeled off and in a slow grinding process. It can be deduced that CAMC was in a stable wear period. Additionally, a small amount of O was found in the cutting area, and thus CAMC also had slight oxidation wear.\\u003c/p\\u003e\\n \\u003cp\\u003eFigure 5(e) and Figure 5(f) shows the flank wear morphology of two tools at the machining length 240m. There was tipping at the cutting edge of BEMC, and a tight adhesive layer was found in these areas. It indicated that tool tipping had occurred at an earlier time. Further elemental analysis results of the wear area shows that the content of C increases and the content of Co decreases at the cutting edge. At this time, the diffusion of Co to the inside led to lack on the surface, resulting in a decrease in the bonding strength between the substrate C particles. So the substrate material fell off together with the bonding, which was the main reason for the formation of severe tool tipping. In this period, the coating peeling of CAMC intensified, and the width of the wear area increased. Additionally, there was a small amount of adhesive layer and tiny notches occurred at the same time. However, since the flank face of CAMC contacted the workpiece more evenly, the heat dissipation conditions were improved while reducing friction. Therefore, the spalling of tool substrate was avoided. The energy spectrum analysis showed that the content of O increased and there was a small amount of Ti at the tipping area. This showed that oxidative wear and slight diffusion wear occurred at the same time.\\u003c/p\\u003e\\n\\u003c/div\\u003e\\n\\u003cdiv class=\\\"Section2\\\" id=\\\"Sec4\\\"\\u003e\\n \\u003ch2\\u003e3.4 Effect of tool wear on surface quality\\u003c/h2\\u003e\\n \\u003cp\\u003eFigure 6(a) and Figure 6(b) shows comparison of the machined surface morphology at the machining length 60 m. It can be observed that outstanding peak and trough appeared on the surface machined by BEMC, and the \\u003cem\\u003eS\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003eq\\u003c/em\\u003e\\u003c/sub\\u003e was 0.679 \\u0026micro;m. Due to the small radius of the ball head, BEMC cut into the workpiece and produced obvious ball pits in the wave trough. In contrast with BEMC, CAMC had a flatter machining surface, with only shallow strip grooves and slight wave crests. Its \\u003cem\\u003eS\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003eq\\u003c/em\\u003e\\u003c/sub\\u003e was 0.467 \\u0026micro;m and smaller than that of BEMC.\\u003c/p\\u003e\\n \\u003cp\\u003eWhen the machining length was 150 m, the two kinds of tools entered into a stable wear stage. At this point, the wear of BEMC was relatively severe. The peak and trough of the machined surface were more remarkable, and reflected in the wave peak height increasing. The maximum height of the peak top \\u003cem\\u003eS\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003ep\\u003c/em\\u003e\\u003c/sub\\u003e was 3.713 \\u0026micro;m. Concurrently the defects at the cutting edge were reflected on the machining surface, and there were bulges along the feed direction at the trough floor (Figure 6(c)). The wave peak on the machining surface of CAMC had also begun to become prominent, and narrow trough had appeared. Compared with BEMC, its surface quality had not significantly decreased. The \\u003cem\\u003eS\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003eq\\u003c/em\\u003e\\u003c/sub\\u003e was 0.565 \\u0026micro;m, which was much smaller than 0.905 \\u0026micro;m of BEMC (Figure 6(d)).\\u003c/p\\u003e\\n \\u003cp\\u003eAs the machining length increased, continuous abrasion and mechanical shock between BEMC and the workpiece led to tool tipping and intensified the squeeze plowing action. Therefore, when the machining length was 240 m, the bulge on the surface was more outstanding, and the ball pit in the wave trough became irregular and more rugged. The peak height increased further, and the \\u003cem\\u003eS\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003eq\\u003c/em\\u003e\\u003c/sub\\u003e reached 1.087 \\u0026micro;m (Figure 6(e)). The surface quality machined by CAMC also dropped to some degree. The uniform wave peak disappeared and was replaced by irregular wave peak and shallow trough. These phenomena were caused by the notches of CAMC and the decrease of machining stability. By contrast, the \\u003cem\\u003eS\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003eq\\u003c/em\\u003e\\u003c/sub\\u003e value of CAMC was only 0.678 \\u0026micro;m, so the surface quality was better (Figure 6(f)).\\u003c/p\\u003e\\n\\u003c/div\\u003e\\n\\u003cdiv class=\\\"Section2\\\" id=\\\"Sec5\\\"\\u003e\\n \\u003ch2\\u003e3.5 Analysis and discussion\\u003c/h2\\u003e\\n \\u003cp\\u003eAccording to the above, the residual height value of CAMC was lower, and the surface quality was better. This paper analyzed the actual processing situation of BEMC and CAMC, and established the mathematical model of residual height. Figure 7 shows the comparison of machined surface residual height after milling by BEMC and CAMC. The residual height of machined surface \\u003cem\\u003eh\\u003c/em\\u003e is:\\u003c/p\\u003e\\n \\u003cp\\u003e\\u003cimg src=\\\"data:image/png;base64,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\\\"\\u003e\\u0026nbsp; (1)\\u003c/p\\u003e\\n \\u003cp\\u003eIn the expressions \\u003cem\\u003eR\\u003c/em\\u003e is the radius of the cutting edge, \\u003cem\\u003eL\\u003c/em\\u003e the processing line spacing.\\u003c/p\\u003e\\n \\u003cp\\u003eAs can be seen from Figure 7, under the condition of the same processing line spacing and milling width, the larger radius cutting edge of CAMC cut into the workpiece, resulting in more uniform thickness and thinner average cutting thickness. Moreover, it can be seen from Exps. (1) that the surface residual height \\u003cem\\u003eh\\u003c/em\\u003e at the two adjacent tool paths overlap of CAMC is lower under the condition of fixed processing row spacing \\u003cem\\u003eL\\u003c/em\\u003e. Thus the surface quality is improved.\\u003c/p\\u003e\\n \\u003cp\\u003eTo investigate the milling forces of the two kinds of tools, it is indispensable to create the milling force model diagram in the normal plane reference frame based on the actual cutting process (Figure 8). The cutting area is equivalent to point \\u003cem\\u003eA\\u003c/em\\u003e. At point \\u003cem\\u003eA\\u003c/em\\u003e, the cutting edge receives a feed force \\u003cem\\u003eF\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003ec\\u003c/em\\u003e\\u003c/sub\\u003e perpendicular to the base plane \\u003cem\\u003eP\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003er\\u003c/em\\u003e\\u003c/sub\\u003e and a tangential force \\u003cem\\u003eF\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003et\\u003c/em\\u003e\\u003c/sub\\u003e directed to the cutting edge center in the normal section \\u003cem\\u003eP\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003en\\u003c/em\\u003e\\u003c/sub\\u003e. The resultant shear force \\u003cem\\u003eF\\u003c/em\\u003e of these two forces can be expressed as follows.\\u003c/p\\u003e\\n \\u003cp\\u003e\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(F=\\\\frac{{{\\\\tau _s} \\\\cdot {a_e} \\\\cdot {H_D}}}{{\\\\sin \\\\phi \\\\cdot \\\\cos (\\\\phi +\\\\eta - \\\\gamma \\u0026apos;)}}\\\\) \\u003c/span\\u003e\\u003c/span\\u003e(2)\\u003c/p\\u003e\\n\\u003c/div\\u003e\\n\\u003cp\\u003eIn the expressions \\u003cem\\u003e\\u0026tau;\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003es\\u003c/em\\u003e\\u003c/sub\\u003e stands for the shear stress, \\u003cem\\u003ea\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003ee\\u003c/em\\u003e\\u003c/sub\\u003e the cutting width, \\u003cem\\u003eH\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003eD\\u003c/em\\u003e\\u003c/sub\\u003e the instantaneous undeformed cutting thickness, \\u003cem\\u003e\\u0026phi;\\u003c/em\\u003e the shear angle, \\u003cem\\u003e\\u0026gamma;\\u003c/em\\u003e\\u0026apos; working rake angle, \\u003cem\\u003e\\u0026eta;\\u003c/em\\u003e the friction angle determined by the experiment.\\u003c/p\\u003e\\n\\u003cp\\u003eTaking into account the differences in cutting performance caused by different cutting areas of the tool, it is necessary to probe the impact of the geometric characteristics on helix angle \\u003cem\\u003e\\u0026beta;\\u003c/em\\u003e. The cutting area of CAMC is the side edge, and its helix angle is 30\\u0026deg;. The cutting area of BEMC is the end edge, both its equivalent helix angle \\u003cem\\u003e\\u0026beta;\\u003c/em\\u003e\\u0026apos; and working rake angle \\u003cem\\u003e\\u0026gamma;\\u003c/em\\u003e\\u0026apos; measured in main section \\u003cem\\u003eP\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003en\\u003c/em\\u003e\\u003c/sub\\u003e vary with the axial position angle \\u003cem\\u003e\\u0026theta;\\u003c/em\\u003e of point \\u003cem\\u003eA\\u003c/em\\u003e, as is shown in the following expression.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(\\\\beta \\u0026apos;=\\\\arccos \\\\left( {\\\\frac{{\\\\cot \\\\beta }}{{\\\\sqrt {{{(\\\\sin \\\\theta )}^4}+{{\\\\left( {\\\\cot \\\\beta } \\\\right)}^2}} }}} \\\\right)\\\\) \\u003c/span\\u003e\\u003c/span\\u003e(3)\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(\\\\gamma \\u0026apos;=sin\\\\gamma {\\\\cos ^2}\\\\beta \\u0026apos;{\\\\text{+}}{\\\\sin ^2}\\\\beta \\u0026apos;\\\\) \\u003c/span\\u003e\\u003c/span\\u003e(4)\\u003c/p\\u003e\\n\\u003cp\\u003eAccording to Exps. (3), the end edge equivalent helix angle of BEMC increases nonlinearly with the axial position angle \\u003cem\\u003e\\u0026theta;\\u003c/em\\u003e and is less than the helix angle of CAMC by 30\\u0026deg;. Compared with BEMC, constant helix angle of the side edge of CAMC makes the cutting process more stable. Moreover, the larger helix angle can effectively decompose the main cutting force into axial direction, which makes the axial force component increase significantly. This is the reason that the decline of \\u003cem\\u003eF\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003ex\\u003c/em\\u003e\\u003c/sub\\u003e and \\u003cem\\u003eF\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003ey\\u003c/em\\u003e\\u003c/sub\\u003e of CAMC is more remarkable than that of \\u003cem\\u003eF\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003ez\\u003c/em\\u003e\\u003c/sub\\u003e (Figure 8). Exps. (4) demonstrates that the working rake angle \\u003cem\\u003e\\u0026gamma;\\u003c/em\\u003e\\u0026apos; of CAMC is larger, which will be mentioned in the calculation of the cutting force later.\\u003c/p\\u003e\\n\\u003cp\\u003eThe other parameters in Exps (2) can be expressed as:\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\({H_D}_{{\\\\hbox{max} }}=\\\\frac{{\\\\sqrt {4{R^2} - {a_e}^{2}} }}{{2\\\\sin \\\\left[ {\\\\arctan (\\\\frac{{\\\\sqrt {4{R^2} - {a_e}^{2}} }}{{{a_e} - 2{f_z}}})} \\\\right]}}\\\\) \\u003c/span\\u003e\\u003c/span\\u003e(5)\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\(\\\\phi {\\\\text{=}}\\\\frac{\\\\pi }{4} - \\\\frac{{\\\\eta - \\\\gamma \\u0026apos;}}{2}\\\\) \\u003c/span\\u003e\\u003c/span\\u003e(6)\\u003c/p\\u003e\\n\\u003cp\\u003eTherefore, the maximum shearing force \\u003cem\\u003eF\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003emax\\u003c/em\\u003e\\u003c/sub\\u003e of a single cutting edge in the cutting process can be obtained.\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cspan class=\\\"InlineEquation\\\"\\u003e\\u003cspan class=\\\"mathinline\\\"\\u003e\\\\({F_{\\\\hbox{max} }}=\\\\frac{{{\\\\tau _s} \\\\cdot {a_e} \\\\cdot \\\\sqrt {4{R^2} - {a_e}^{2}} }}{{2\\\\sin \\\\left[ {\\\\arctan (\\\\frac{{\\\\sqrt {4{R^2} - {a_e}^{2}} }}{{{a_e} - 2{f_z}}})} \\\\right] \\\\cdot \\\\sin (\\\\frac{\\\\pi }{4} - \\\\frac{{\\\\eta - \\\\gamma \\u0026apos;}}{2}) \\\\cdot \\\\cos (\\\\frac{\\\\pi }{4}+\\\\frac{{\\\\eta - \\\\gamma \\u0026apos;}}{2})}}\\\\) \\u003c/span\\u003e\\u003c/span\\u003e(7)\\u003c/p\\u003e\\n\\u003cp\\u003eIt can be seen from Exps. (5) that CAMC reduces the maximum instantaneous cutting thickness \\u003cem\\u003eH\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003eDmax\\u003c/em\\u003e\\u003c/sub\\u003e for its larger side edge radius \\u003cem\\u003eR\\u003c/em\\u003e. Therefore, the conclusion can be drawn from Exps. (7) that the large working rake angle of CAMC and the cutting thickness thinning mechanism reduce the maximum cutting force during the cutting process jointly. Furthermore, the tool wear was effectively relieved. It is worth noting that the larger radius and flatter cutting edge of CAMC make the wear area dispersed and uniform to avoid heat concentration. Consequently, this also has a positive effect on prolonging tool life.\\u003c/p\\u003e\"},{\"header\":\"4 Conclusions\",\"content\":\"\\u003cp\\u003eIn this paper, the cutting property comparison study of ball-end milling cutters (BEMC) and circular-arc milling cutters (CAMC) was carried out. The comparative analysis was made of milling forces, tool wear and surface quality. The following conclusions were obtained.\\u003c/p\\u003e \\u003cp\\u003e(1) In contrast with BEMC, the tangential force and radial force decreased obviously under the action of cutting thickness thinning mechanism. In addition, the tangential force fluctuation amplitude of CAMC was significantly smaller than that of BEMC, which represented excellent dynamic processing performance.\\u003c/p\\u003e \\u003cp\\u003e(2) The flank face of CAMC was dominated by adhesive wear, and the wear area was near the cutting edge and narrower. After a long cutting time, obvious oxidation wear was observed. The width and depth of the wear area increased slowly. The final failure occurred with the appearance of the notches.\\u003c/p\\u003e \\u003cp\\u003e(3) In the whole cutting process, CAMC had better surface quality. There was no obvious peak and trough in machined surface, and the surface roughness \\u003cem\\u003eS\\u003c/em\\u003e\\u003csub\\u003e\\u003cem\\u003eq\\u003c/em\\u003e\\u003c/sub\\u003e was kept at a low level.\\u003c/p\\u003e \\u003cp\\u003e(4) The machined surface produced by CAMC had lower residual height under the action of large cutting edge radius. Compared with BEMC, the large working rake angle of CAMC and the reduction of cutting thickness decreased the maximum cutting force. And the flatter cutting edge makes the heat even, effectively relieving tool wear.\\u003c/p\\u003e\"},{\"header\":\"Declarations\",\"content\":\"\\u003cp\\u003e\\u003cstrong\\u003eAcknowledgements\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eNot applicable\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eFunding\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eSupported by National Natural Science Foundation of China (Grant No. 51975168). \\u003cstrong\\u003e\\u0026nbsp;\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eAvailability of data and materials\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eAll data generated or analysed during this study are included in this published article.\\u003cstrong\\u003e\\u0026nbsp;\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eAuthors\\u0026rsquo; contributions\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThe author\\u0026rsquo; contributions are as follows: Tao Chen, has organized the project, designed the experiments, and written the manuscript; Gang Liu, has designed the experiments, analyzed and arranged data, and written the manuscript; Jia-Qiang Liu, has conducted the experiments, and collected and analyzed data; Hui Xiao, has conducted the experiments, and collected and analyzed data; Chun-Hui Li, has reviewed the manuscript; Xian-Li Liu, has reviewed the manuscript.\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eCompeting interests\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eThe authors declare no competing financial interests.\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eConsent for publication\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eNot applicable\\u0026nbsp;\\u003c/p\\u003e\\n\\u003cp\\u003e\\u003cstrong\\u003eEthics approval and consent to participate\\u003c/strong\\u003e\\u003c/p\\u003e\\n\\u003cp\\u003eNot applicable\\u003c/p\\u003e\"},{\"header\":\"References\",\"content\":\"\\u003col\\u003e\\u003cli\\u003e\\u003cspan\\u003eA Pramanik. Problems and solutions in machining of titanium alloys. The International Journal of Advanced Manufacturing Technology, 2014, 70(5\\u0026ndash;8): 919\\u0026ndash;928.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eC Veiga, J P Davim, A J R Loureiro. Review on machinability of titanium alloys: The process perspective. Reviews on advanced materials science, 2013, 34(2): 148\\u0026ndash;164.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eW Polini, S Turchetta. Cutting force, tool life and surface integrity in milling of titanium alloy Ti-6Al-4V with coated carbide tools. \\u003cem\\u003eProceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture\\u003c/em\\u003e, 2016, 230(4): 694\\u0026ndash;700.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eH Jung, T Hayasaka, E Shamoto, et al. 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Flank Milling for Blisk with a Barrel Ball Milling Cutter. Key Engineering Materials, 2009, 407\\u0026ndash;408: 202\\u0026ndash;206.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eV Krishnaraj, S Samsudeensadham, R Sindhumathi, et al. A study on High Speed End Milling of Titanium Alloy. Procedia Engineering, 2014, 97(97): 251\\u0026ndash;257.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eT Chen, Y S Wang, W J Gao, et al. Comparative study on the cutting performance of self-propelled rotary cutters and indexable cutters in milling TC11 titanium alloy. The International Journal of Advanced Manufacturing Technology, 2020, 111(9): 2749\\u0026ndash;2758.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eQ Shi, L Li, N He, et al. Experimental study in high speed milling of titanium alloy TC21. The International Journal of Advanced Manufacturing Technology, 2016, 64(1\\u0026ndash;4): 49\\u0026ndash;54.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eA K M N Amin, A F Ismail, M K N Khairusshima. Effectiveness of uncoated WC-Co and PCD inserts in end milling of titanium alloy-Ti-6Al-4V. Journal of Materials Processing Tech, 2007, 192\\u0026ndash;193: 147\\u0026ndash;158.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eH H Su, P Liu, Y C Fu, et al. Tool Life and Surface Integrity in High-speed Milling of Titanium Alloy TA15 with PCD/PCBN Tools. Chinese Journal of Aeronautics, 2012, 25(5): 784\\u0026ndash;790.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eD Yan, D Zhang, M Luo. Optimization of Barrel Cutter for Five-axis Flank-milling Based on Approximation of Tool Envelope Surface. Computer Aided Design \\u0026amp; Applications, 2015, 12(6): 717\\u0026ndash;722.\\u003c/span\\u003e\\u003c/li\\u003e \\u003cli\\u003e\\u003cspan\\u003eM Luo, D Q Yan, B H Wu, et al. Barrel cutter design and toolpath planning for high-efficiency machining of freeform surface. The International Journal of Advanced Manufacturing Technology, 2016, 85(9\\u0026ndash;12): 2495\\u0026ndash;2503.\\u003c/span\\u003e\\u003c/li\\u003e \\u003c/ol\\u003e\"}],\"fulltextSource\":\"\",\"fullText\":\"\",\"funders\":[],\"hasAdminPriorityOnWorkflow\":false,\"hasManuscriptDocX\":true,\"hasOptedInToPreprint\":true,\"hasPassedJournalQc\":\"\",\"hasAnyPriority\":false,\"hideJournal\":false,\"highlight\":\"\",\"institution\":\"\",\"isAcceptedByJournal\":true,\"isAuthorSuppliedPdf\":false,\"isDeskRejected\":\"\",\"isHiddenFromSearch\":false,\"isInQc\":false,\"isInWorkflow\":true,\"isPdf\":false,\"isPdfUpToDate\":true,\"isWithdrawnOrRetracted\":false,\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"chinese-journal-of-mechanical-engineering\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":false,\"externalIdentity\":\"chme\",\"sideBox\":\"Learn more about [Chinese Journal of Mechanical Engineering](https://cjme.springeropen.com)\",\"snPcode\":\"\",\"submissionUrl\":\"https://www.editorialmanager.com/chme/default.aspx\",\"title\":\"Chinese Journal of Mechanical Engineering\",\"twitterHandle\":\"@SpringerOpen\",\"acdcEnabled\":true,\"dfaEnabled\":true,\"editorialSystem\":\"em\",\"reportingPortfolio\":\"BMC/SO AJ\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":true},\"keywords\":\"Circular-arc milling cutter, Titanium alloy, Ball-end milling cutter, Milling force, Tool wear\",\"lastPublishedDoi\":\"10.21203/rs.3.rs-1268000/v1\",\"lastPublishedDoiUrl\":\"https://doi.org/10.21203/rs.3.rs-1268000/v1\",\"license\":{\"name\":\"CC BY 4.0\",\"url\":\"https://creativecommons.org/licenses/by/4.0/\"},\"manuscriptAbstract\":\"Titanium alloy has been applied in the field of aerospace manufacturing for its high specific strength and hardness. Nonetheless, these properties also cause general problems in the machining, such as processing inefficiency, serious wear, poor workpiece face quality, etc. Aiming at the above problems, this paper carried out a comparative experimental study on titanium alloy milling based on the CAMC and BEMC. The variation law of cutting force and surface quality of the two tools was obtained, and the wear mechanism was analyzed. The conclusion is that in contrast with BEMC, under the action of cutting thickness thinning mechanism, the force of CAMC was less, and its fluctuation was more stable. The flank wear was uniform and near the cutting edge, and the wear rate was slower. In the early period, the wear mechanism of CAMC was mainly adhesion. Gradually, oxidative wear also occurred with milling. Furthermore, the surface residual height of CAMC was lower. There is no obvious peak and trough accompanied with less surface defects.\",\"manuscriptTitle\":\"Experimental Study on Titanium Alloy Cutting Property and Wear Mechanism with Circular-arc Milling Cutters\",\"msid\":\"\",\"msnumber\":\"\",\"nonDraftVersions\":[{\"code\":1,\"date\":\"2022-03-22 14:31:45\",\"doi\":\"10.21203/rs.3.rs-1268000/v1\",\"editorialEvents\":[{\"type\":\"communityComments\",\"content\":0},{\"type\":\"editorInvitedReview\",\"content\":\"\",\"date\":\"2022-03-19T10:08:07+00:00\",\"index\":0,\"fulltext\":\"\"},{\"type\":\"reviewersInvited\",\"content\":\"\",\"date\":\"2022-03-17T12:21:54+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"editorInvited\",\"content\":\"Chinese Journal of Mechanical Engineering\",\"date\":\"2022-02-25T09:21:13+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"editorAssigned\",\"content\":\"\",\"date\":\"2022-01-18T15:02:53+00:00\",\"index\":\"\",\"fulltext\":\"\"},{\"type\":\"submitted\",\"content\":\"Chinese Journal of Mechanical Engineering\",\"date\":\"2022-01-17T04:22:35+00:00\",\"index\":\"\",\"fulltext\":\"\"}],\"status\":\"published\",\"journal\":{\"display\":true,\"email\":\"info@researchsquare.com\",\"identity\":\"chinese-journal-of-mechanical-engineering\",\"isNatureJournal\":false,\"hasQc\":true,\"allowDirectSubmit\":false,\"externalIdentity\":\"chme\",\"sideBox\":\"Learn more about [Chinese Journal of Mechanical Engineering](https://cjme.springeropen.com)\",\"snPcode\":\"\",\"submissionUrl\":\"https://www.editorialmanager.com/chme/default.aspx\",\"title\":\"Chinese Journal of Mechanical Engineering\",\"twitterHandle\":\"@SpringerOpen\",\"acdcEnabled\":true,\"dfaEnabled\":true,\"editorialSystem\":\"em\",\"reportingPortfolio\":\"BMC/SO AJ\",\"inReviewEnabled\":true,\"inReviewRevisionsEnabled\":true}}],\"origin\":\"\",\"ownerIdentity\":\"0cec3ad0-719a-44c9-9639-c078217fb874\",\"owner\":[],\"postedDate\":\"March 22nd, 2022\",\"published\":true,\"recentEditorialEvents\":[],\"rejectedJournal\":[],\"revision\":\"\",\"amendment\":\"\",\"status\":\"published-in-journal\",\"subjectAreas\":[],\"tags\":[],\"updatedAt\":\"2023-10-16T20:50:51+00:00\",\"versionOfRecord\":{\"articleIdentity\":\"rs-1268000\",\"link\":\"https://doi.org/10.1186/s10033-023-00887-5\",\"journal\":{\"identity\":\"chinese-journal-of-mechanical-engineering\",\"isVorOnly\":false,\"title\":\"Chinese Journal of Mechanical Engineering\"},\"publishedOn\":\"2023-04-28 20:38:35\",\"publishedOnDateReadable\":\"April 28th, 2023\"},\"versionCreatedAt\":\"2022-03-22 14:31:45\",\"video\":\"\",\"vorDoi\":\"10.1186/s10033-023-00887-5\",\"vorDoiUrl\":\"https://doi.org/10.1186/s10033-023-00887-5\",\"workflowStages\":[]},\"version\":\"v1\",\"identity\":\"rs-1268000\",\"journalConfig\":\"researchsquare\"},\"__N_SSP\":true},\"page\":\"/article/[identity]/[[...version]]\",\"query\":{\"redirect\":\"/article/rs-1268000\",\"identity\":\"rs-1268000\",\"version\":[\"v1\"]},\"buildId\":\"_2-kVJe1T_tPrBINL-cwx\",\"isFallback\":false,\"isExperimentalCompile\":false,\"dynamicIds\":[84888],\"gssp\":true,\"scriptLoader\":[]}","source_license":"CC-BY-4.0","license_restricted":false}