(1. 中国科学院 金属研究所，沈阳 110016；2. 北京航空制造工程研究所，北京 100024)
摘 要: 研究TC17和Ti60异材钛合金电子束焊接接头的显微组织和显微硬度分布特征。结果表明：异材焊接接头的显微组织呈不均匀分布，焊接接头熔合区中由大量针状α′相，少量α相和β相组成，Ti60的热影响区在焊接过程中发生了马氏体转变，由针状的α′相+等轴α相和少量β相组成；TC17的热影响区由针状α′相、等轴α相和亚稳β相组成。组织的不均匀分布导致焊接接头显微硬度分布不均匀，熔合区中的硬度最高， TC17的中热影响区中硬度最低。
关键字: Ti60钛合金；TC17钛合金；异材电子束焊接；显微组织；显微硬度
（1. Institute of Metal Research, The Chinese Academy of Sciences, Shenyang 110016, China;
2. Beijing Aeronautical Manufacturing Technology Research Institute, Beijing 100024, China）
Abstract:The microstructure and microhardness of dissimilar joint of a near α titanium alloy Ti60 and a β-rich, α+β titanium alloy TC17 were studied using electron beam welding technique. The results show that the microstructure is not uniform in different regions of the joint. The fusion zone is constituted of great amount of acicular α′ phase, small amount of α phase and retained β phase. Martensitic transmission occurs in the heat-affected zone (HAZ) of Ti60 alloy, so the HAZ of Ti60 alloy is constituted of acicular α′ phase, equiaxial α phase and samll amount of β phase. The HAZ of TC17 titanium alloy is constituted of acicular α′ phase, equiaxial α phase and metastable β phase. The microhardness of the joint distributes unevenly due to gradual microstructure of the joint. The microhardness of fusion zone (FZ) is the highest and the microhardness of the middle HAZ of TC17 is the lowest.
Key words: Ti60 titanium alloy; TC17 titanium alloy; dissimilar electron beam welding; microstructure; micro-hardness
