等离子电弧双丝增材制造Ti-48Al合金组织特征  

Investigation on microstructure characteristics of Ti-48Al alloy fabricated using twin-wire directed energy depositionplasma arc

作　　者：王林 华学明[1] 沈忱 张跃龙[1] 李芳[1] 周雯露 丁煜瀚 WANG Lin;HUA Xueming;SHEN Chen;ZHANG Yuelong;LI Fang;ZHOU Wenlu;DING Yuhan(Shanghai Key Laboratory of Materials Laser Processing and Modification,School of Materials Science and Engineering,Shanghai Jiao Tong University,Shanghai,200240,China)

机构地区：[1]上海交通大学,上海市激光制造与材料改性重点实验室,上海200240

出　　处：《焊接学报》2024年第2期1-6,I0003,共7页Transactions of The China Welding Institution

基　　金：国家自然科学基金“联合基金项目”(No.U1937601);上海市2019年度“科技创新行动计划”高新技术领域项目(19511106400);上海市科学技术委员会“扬帆计划项目”(19YF1422700).

摘　　要：采用等离子电弧双丝增材制造技术成功制备了Ti-48Al合金(at.%),并对其沉积态和热处理后的组织特征进行了系统地研究.结果表明,沉积态Ti-48Al合金主要由α2相和γ相组成,沿着沉积方向,沉积态组织呈现由树枝晶区和片层晶团区交替分布的不均匀性特征,并且在树枝晶区存在严重的枝晶间Al元素偏析现象.在1 340℃/10 h/炉冷热处理后,不均匀的沉积态组织转变为晶粒尺寸细小的双态组织,Ti-48Al合金的微观组织的不均匀性获得明显改善,并且α2相含量显著增加,组织的择优取向减弱.Ti-48Al alloy is fabricated successfully using plasma arc powred twin wire-directed energy deposition-arc,and its microstructure characteristic before and after heat treatment is systematically investigated.The results show that asdeposited Ti-48Al alloy consists ofα2 andγphase.The microstructure is characterized by the alternatively distributed dendritic grain and fully lamellar colony along the building direction for as-deposited Ti-48Al alloy,and there is interdendritic Al element segregation in the dendritic grain region.After heat treatment in 1340℃/10 h/furnace cooling,the duplex microstructure with fine grain size is obtained,and the microstructure heterogeneity is significantly improved,theα2 phase content is obviously increased,the preferred orientation of microstructure is also weakened.

关 键 词：电弧增材制造 TIAL合金 微观组织 热处理 

分 类 号：TG444.4[金属学及工艺—焊接]