热处理对TiAl基合金相变和显微组织的影响  

Effect of heat treatment on phase transformation and microstructure of TiAl - based alloys

作　　者：彭超群[1] 黄伯云[1] 贺跃辉[1] 

机构地区：[1]中南大学 粉末冶金国家重点实验室,湖南长沙410083

出　　处：《材料科学与工艺》2002年第3期331-336,共6页Materials Science and Technology

基　　金：国家"八六三"高技术基金资助项目(715-005-0040).

摘　　要：TiAl基合金净形成形是克服其难加工成形的有效方法,但该合金铸态组织较粗大,不利于提高其综合性能,如何细化该合金的微观组织成为当前研究热点之一.本文重点讨论了通过热处理改变TiAl基合金微观组织的技术途径,包括双相区热处理、双温热处理、循环热处理、快速加热循环热处理等,并分析了各种热处理条件下组织演变的微观机制.其中快速循环热处理对细化原始组织效果最为显著.Near net shape forming is a vialid method to overcome the poor processing properties of TiAl - based alloys. However, the cast microstructure is thus very coarse and the ductility is not acceptable. How lo refine the micro-structure is a main field for improving the ductility and other properties. This paper reviewed the recent developments in the microstructure refining of TiAl alloys with special heat treatments, including heat treatment in α + γ double phase zone, double temperature treatment, cyclic heat treatment and rapidly heating cyclic treatment. The phase transformation mechanism during heat treatments were discussed. The advantages of rapd cyclic trentment was emhasized.

关 键 词：显微组织 TIAL基合金 热处理 相变 钛铝合金 连续冷却 

分 类 号：TG166[金属学及工艺—热处理]