摘要
对含镍０２％～０５％（原子百分数，下同）的铸造Ｔｉ４６５Ａｌ２５Ｖ１０Ｃｒ（％）合金进行１１５０℃×１４４ｈ等温热处理，使铸态粗大、不均匀的层片组织分解为均匀、细小、等轴的近γ组织，然后将其重新加热到１３７０℃×（５～１０）ｍｉｎ后冷却，得到层片团等轴、细小、均匀的全层片组织。对镍微合金化简化铸造钛铝合金组织均匀化、细化热处理工艺的作用机理及含镍的钛铝合金细小全层片组织的形成机理作了分析讨论。
The heat treatment at 1150℃ for 144 hours was successfully applied to transform the coarse,inhomogeneous as cast microstructure of the cast Ti 46 5Al 2 5V 1 0Cr(at%) alloy containing (0 2～0 5)at% Ni to a fine,homogeneous equiaxed near gamma (NG) microstructure Then this NG microstructure was reheated up to 1370℃ to obtain the fine fully lamellar(FFL) microstructure Therefore,the heat treatment employed to homogenize and refine as cast microstructure of cast TiAl alloy was dramatically simplified through bearing (0 2～0 5)at% Ni The effects of the Ni microalloying were suggested as that the Ni enlarge the γ phase zone of TiAl alloys and so increase the energe of the α 2 or α→γ transformation at 1150℃ which intensify the breakdown of the lamellae and then promote the segmental continuous coarsening of the lamellae The transformation mechanisms of the obtained FFL microstructure with equiaxed colonies were also discussed
出处
《金属热处理》
CAS
CSCD
北大核心
1999年第1期16-17,共2页
Heat Treatment of Metals
