Abstract
Electron beam selective melting (EBM) and selective laser melting (SLM) are regarded as significant manufacturing processes for near-net-shaped Ti6Al4V components. Generally, in the conventional EBM process, preheating is necessitated to avoid “smoke” caused by the charging of electrons. In the conventional SLM process, laser as an energy source without the risk of “smoke” can be employed to melt metal powder at low temperatures. However, because of the low absorption rate of laser, the powder bed temperature cannot reach a high level. It is difficult to obtain as-built TiAl4V with favorable comprehensive properties via conventional EBM or SLM. Hence, two types of electron beam and laser hybrid preheating (EB-LHP) combined with selective melting strategies are proposed. Using laser to preheat powder allows EBM to be performed at a low powder bed temperature (EBM-LT), whereas using an electron beam to preheat powder allows SLM to be performed at a high powder bed temperature (SLM-HT). Ti6Al4V samples are fabricated using two different manufacturing strategies (i.e., EBM-LT and SLM-HT) and two conventional processes, i.e., EBM at a high powder bed temperature (EBM-HT) and SLM at a low powder bed temperature (SLM-LT). The temperature-dependent surface quality, microstructure, density, and mechanical properties of the as-built Ti6Al4V samples are characterized and compared. Results show that EBM-LT Ti6Al4V exhibits a higher ultimate tensile strength (981±43 MPa) and a lower elongation (12.2%±2.3%) than EBM-HT Ti6Al4V owing to the presence of α′ martensite. The SLM-HT Ti6Al4V possesses the highest ultimate tensile strength (1,059±62 MPa) and an elongation (14.8%±4.0%) comparable to that of the EBM-HT Ti6Al4V (16.6%±1.2%).
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References
Rafi H K, Karthik N V, Gong H J, et al. Microstructures and mechanical properties of Ti6Al4V parts fabricated by selective laser melting and electron beam melting. J. Mater. Eng. Perform., 2013, 22(12): 3872–3883.
Zhao X L, Li S J, Zhang M, et al. Comparison of the microstructures and mechanical properties of Ti-6Al-4V fabricated by selective laser melting and electron beam melting. Mater. Design, 2016, 95: 21–31.
Chen W, Li Z Q. Additive manufacturing of titanium aluminides. In: Froes F, Boyer R (Eds.), Additive Manufacturing for the Aerospace Industry, Amsterdam: Elsevier Inc., 2019: 235–263.
Cordero Z C, Meyer H M, Nandwana P, et al. Powder bed charging during electron-beam additive manufacturing. Acta Mater., 2017, 124: 437–445.
Bartlett J L, Li X D. An overview of residual stresses in metal powder bed fusion. Addit. Manuf., 2019, 27: 131–149.
Polmear I, StJohn D, Nie J F, et al. Light alloys, 5th Ed., Elsevier Ltd., 2017: 369–460.
Liu S Y, Shin Y C. Additive manufacturing of Ti6Al4V alloy: A review. Mater. Design, 2019, 164, 107552.
Vayssette B, Saintier N, Brugger C, et al. Surface roughness of Ti-6Al-4V parts obtained by SLM and EBM: Effect on the high cycle fatigue life. Procedia Eng., 2018, 213: 89–97.
Haubrich J, Gussone J, Barriobero-Vila P, et al. The role of lattice defects, element partitioning and intrinsic heat effects on the microstructure in selective laser melted Ti-6Al-4V. Acta Mater., 2019, 167: 136–148.
Liu J W, Sun Q D, Zhou C A, et al. Achieving Ti6Al4V alloys with both high strength and ductility via selective laser melting. Mat. Sci. Eng. A, 2019, 766:138319.
Xu Y L, Zhang D Y, Guo Y W, et al. Microstructural tailoring of as-selective laser melted Ti6Al4V alloy for high mechanical properties. J. Alloy. Compd., 2020, 816: 152536.
Gu D D, Hagedorn Y C, Meiners W, et al. Densification behavior, microstructure evolution, and wear performance of selective laser melting processed commercially pure titanium. Acta Mater., 2012, 60(9): 3849–3860.
Liu C Y, Mai Z K, Yan D, et al. Effect of hot isostatic pressing on microstructures and mechanical properties of Ti6Al4V fabricated by electron beam melting. Metals, 2020, 10(5): 593.
Liang Z L, Sun Z G, Zhang W S, et al. The effect of heat treatment on microstructure evolution and tensile properties of selective laser melted Ti6Al4V alloy. J. Alloy. Compd., 2019, 782: 1041–1048.
Ali H, Ma L, Ghadbeigi H, et al. In-situ residual stress reduction, martensitic decomposition and mechanical properties enhancement through high temperature powder bed pre-heating of selective laser melted Ti6Al4V. Mat. Sci. Eng. A, 2017, 695: 211–220.
Leung C L A, Tosi R, Muzangaza E, et al. Effect of preheating on the thermal, microstructural and mechanical properties of selective electron beam melted Ti-6Al-4V components. Mater. Des., 2019, 174, 107792.
Cao J, Nash P. Numerical simulation of the effects of preheating on electron beam additive manufactured Ti-6Al-4V build plate. Mater. Sci. Forum, 2017, 879: 274–278.
Zhou B, Zhou J, Li H X, et al. Fabrication and characterization of Ti6Al4V by selective electron beam and laser hybrid melting. In: Proceedings of the 28th Annual International-Solid Freeform Fabrication Symposium, 2017: 1924–1934.
Zhou B, Zhou J, Li H X, et al. A study of the microstructures and mechanical properties of Ti6Al4V fabricated by SLM under vacuum. Mater. Sci. Eng. A, 2018, 724: 1–10.
Fousova M, Vojtech D, Doubrava K, et al. Influence of inherent surface and internal defects on mechanical properties of additively manufactured Ti6Al4V alloy: Comparison between selective laser melting and electron beam melting. Materials, 2018, 11(4): 537.
Li P, Warner D H, Fatemi A, et al. Critical assessment of the fatigue performance of additively manufactured Ti-6Al-4V and perspective for future research. Int. J. Fatigue, 2016, 85: 130–143.
Kurzynowski T, Madeja M, Dziedzic R, et al. The effect of EBM process parameters on porosity and microstructure of Ti-5Al-5Mo-5V-1Cr-1Fe alloy. Scanning, 2019: 2903920.
Chen Z E, Cao S, Wu X H, et al. Surface roughness and fatigue properties of selective laser melted Ti-6Al-4V alloy. In: Froes F, Boyer R (Eds.), Additive Manufacturing for the Aerospace Industry. Amsterdam: Elsevier Inc., 2019: 283–299.
Ahmed T, Rack H J. Phase transformations during cooling in α+β titanium alloys. Mater. Sci. Eng. A, 1998, 243(1–2): 206–211.
Al-Bermani S S, Blackmore M L, Zhang W, et al. The origin of microstructural diversity, texture, and mechanical properties in electron beam melted Ti-6Al-4V. Metall. Mater. Trans. A, 2010, 41(13): 3422–3434.
Gil Mur F X, Rodríguez D, Planell J A. Influence of tempering temperature and time on the α′-Ti-6Al-4V martensite. J. Alloy. Compd., 1996, 234(2): 287–289.
Galarraga H, Warren R J, Lados D A, et al. Effects of heat treatments on microstructure and properties of Ti-6Al-4V ELI alloy fabricated by electron beam melting (EBM). Mater. Sci. Eng. A, 2017, 685: 417–428.
Acknowledgements
This work was financially supported by the National Key R&D Program (2018YFB1105200), 111 Project (B17026), and Open Fund of State Key Laboratory of Advanced Forming Technology and Equipment (SKL2019006).
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Lei Zhang Male, born in 1977, Ph. D., Associate Professor. His research mainly focuses on additive manufacturing, bio fabrication, and forging technology. To date, he has published about 30 papers in SCI-indexed journals.
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Hao, Mh., Zhang, L., Zhou, B. et al. Performance of Ti6Al4V fabricated by electron beam and laser hybrid preheating and selective melting strategy. China Foundry 18, 351–359 (2021). https://doi.org/10.1007/s41230-021-1039-1
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DOI: https://doi.org/10.1007/s41230-021-1039-1