Refinement of α′Martensite by Oxygen in Selective Laser Melted Ti-6Al-4V  

作　　者：Hasfi FNurly Jinhu Zhang Dechun Ren Yusheng Cai Haibin Ji Dongsheng Xu Zhicheng Dong Hao Wang Qingmiao Hu Jiafeng Lei Rui Yang 

机构地区：[1]School of Materials Science and Engineering,University of Science and Technology of China,Shenyang 110016,China [2]Shi-Changxu Innovation Center for Advanced Materials,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China [3]School of Materials and Chemistry/Interdisciplinary Centre for Additive Manufacturing,University of Shanghai for Science and Technology,Shanghai 200093,China [4]Centre for Adaptive System Engineering,ShanghaiTech University,Shanghai 201210,China

出　　处：《Acta Metallurgica Sinica(English Letters)》2024年第5期777-792,共16页金属学报（英文版）

基　　金：financially supported by the National Natural Science Foundation of China(No.52205431);the CAS Interdisciplinary Innovation Team Project(No.JCTD-2020-10)。

摘　　要：Oxygen is crucial in influencing the microstructure evolution of selective laser melted(SLMed)Ti–6Al–4V,significantly impacting its applicability in various sectors.Therefore,this study investigates the influnce of oxygen on microstructure evolution,particularlyα′martensite transformation and refinement mechanisms.Four alloys,Ti–6Al–4V–xO(x=0.11,0.16,0.21,and 0.25 wt%),were fabricated by the SLM process.The martensite start temperature(M_(s))of Ti–6Al–4V,as evaluated by computation,is 656.8°C,and oxygen was found to increase the M_(s) by about 10°C per 0.1 wt%.The SLMed alloy samples exhibit[001]_(β)growth texture along the build direction.Crystallographic analysis of martensite morphology suggests internal twinning on{1011}planes as the lattice invariant strain,which becomes more predominant with increasing oxygen content.Refinement of α′martensite plates by oxygen is due to increased lattice distortion,reduced prior β grain size,and oxygen segregation toβgrain boundaries.Our findings contribute to improving the understanding of the effect of oxygen on the transformation mechanism ofα′martensite during SLM of Ti–6Al–4V.

关 键 词：Selective laser melting α′Martensite Martensite start temperature OXYGEN TI-6AL-4V 

分 类 号：TG665[金属学及工艺—金属切削加工及机床] TG146.15[一般工业技术—材料科学与工程]