Enhancing work hardening and ductility in additively manufacturedβTi:roles played by grain orientation,morphology and substructure  

作　　者：Ahmad Zafari Edward Wen Chiek Lui Mogeng Li Kenong Xia 

机构地区：[1]Department of Mechanical Engineering,The University of Melbourne,Victoria 3010,Australia [2]Centre for Additive Manufacturing,School of Engineering,RMIT University,Melbourne,VIC 3000,Australia [3]Physics of Fluids Group,Max Planck Center for Complex Fluid Dynamics,J.M.Burgers Center for Fluid Dynamics and MESA+Research Institute,Department of Science and Technology,University of Twente,7500AE Enschede,the Netherlands

出　　处：《Journal of Materials Science & Technology》2022年第10期131-141,共11页材料科学技术（英文版）

基　　金：supported by the Australian Research Council(No.DP190103557);the University of Melbourne(No.ECRG20)。

摘　　要：A metastableβTi alloy was additively manufactured by laser powder bed fusion(LPBF).Tensile testing along the build direction of the as-LPBF material(LPBF-0°)revealed signifcant work softening immediately following yielding with no uniform deformation.By contrast,substantial work hardening and uniform elongation well over 10%were achieved perpendicular to the build direction(LPBF-90°).Similar effects were obtained in the build direction after super transus heat treatment(LPBF-0°+HT)although the strength was slightly lowered.In addition,the yield drop phenomenon observed in both orientations of the as-LPBF materials disappeared after HT.The enhanced work hardening ability,and thus ductility,can be attributed to increased interactions of slip bands/slip bands owing to additional{112}<111>slip systems becoming operative in LPBF-0°+HT and LPBF-90°while LPBF-0°was dominated by{110}<111>only.The other variations after HT may be related to the coarsening of grain structure and removal of specifc substructures in the as-LPBF microstructure.

关 键 词：βtitanium Work hardening ANISOTROPY Equiaxed microstructure Slip band Laser powder bed fusion 

分 类 号：TG146.23[一般工业技术—材料科学与工程] TG665[金属学及工艺—金属材料]