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研究了锻造ＴｉＡｌ基合金在１１８０到１３２０℃热处理时的晶粒长大过程，并分析了在等温热处理时晶粒长大的动力学．在ａ相转变温度 Ｔａ以上等温热处理时，晶粒迅速长大．晶粒长大因子为 ２．４；在 Ｔａ以下等温热处理时，当热处理时间由 １０ ｍｉｎ延长至４ｈ时，α晶粒不断长大，γ体积分数 γ逐渐变化至平衡值，而γ晶粒尺寸Ｄγ增长较小。继续延长热处理时间。显微组织没有明显的变化，α晶粒尺寸的极限值Ｄα０约为０．６５Ｄｒ／ ｒ提高热处理温度时、ａ晶粒长大速度加快在１１８０，１２２０；１２６０和１３００ ℃热处理时，ａ晶粒长大因子分别为２．９，２．８，２．６５和２．５．
The grain growth process of forged TiAl-based alloys during heat treatment at 1180-1320 ℃ was studied. The kinetics of grain growth during isothermal heat treatment was also analyzed. At the a-phase transformation temperature Ta above isothermal heat treatment, the rapid growth of grains. The grain growth factor is 2.4. When isothermal heat treatment below Ta, the α grains grow up gradually when the heat treatment time is prolonged from 10 min to 4 h, the γ volume fraction γ gradually changes to the equilibrium value, while the γ crystal Grain size Dγ increased less. Continue to extend the heat treatment time. There is no obvious change in microstructure. The limit value of α grain size is about 0.65Dr / r. When the heat treatment temperature is increased, the growth speed of a grains grows faster at 1180, 1220 and 1260 and 1300 ℃, The growth factors were 2.9, 2.8, 2.65 and 2.5 respectively.