热处理对粉末冶金TiAl双态组织与性能的影响  

Effect of heat treatment on duplex microstructure and mechanical properties of PM TiAl alloy

作　　者：苏美科[1] 郑立静[1] 张虎[1] 郎泽保[2] 

机构地区：[1]北京航空航天大学材料科学与工程学院,北京100191 [2]航天材料及工艺研究所,北京100076

出　　处：《北京航空航天大学学报》2013年第4期549-552,558,共5页Journal of Beijing University of Aeronautics and Astronautics

摘　　要：对粉末冶金制备的Ti-46Al-2Cr-2Nb-(B,W)(at%)合金在1 280℃进行直接热处理,通过3种不同冷却速度获得了不同的双态组织.当冷却速度为50℃/min时,组织中的α晶粒通过析出γ片形成片层团,获得主要由片层团和γ相组成的双态组织,组织中过高片层体积分数导致拉伸延长率不高;而冷却速度为10℃/min和5℃/min时,形成了主要由α2晶粒和γ相组成的双相组织,α2晶粒的存在进一步降低了材料室温延长率.Ti-46A1-2Cr-2Nb-（ B ,W）（ at% ） alloy prepared by powder metallurgy was direct heat treated and microstructures of the alloy were obtained by cooling at different cooling rates. Results show that duplex microstructure consisting mainly of fine equiaxed γ grains and lamellar colonies were obtained at cooling rate of 50 ~C/min. High volume fractions of lamellar colonies result in low elongation. Structure consisting mainly of fine γ grains and α2 grains were formed at cooling rate of 10℃/min and 5℃/min. Presence of α2 phase fur- ther reduced the elongation.

关 键 词：粉末冶金 TIAL合金 热处理 力学性能 

分 类 号：TG146.2[一般工业技术—材料科学与工程]