热连轧GH4169合金的晶粒长大行为

Study on Grain Growth of Hot Continuous Rolled GH4169 Superalloy

摘要:

对热连轧 (HCR) GH4169合金在固溶处理过程中晶粒长大行为进行系统研究。结果表明，该合金d相溶解温度在990~1000 ℃之间，d相对晶粒长大有显著阻碍作用，在低于d相溶解温度进行固溶处理时，析出的d相使得晶粒长大缓慢；在高于d相溶解温度以上时，晶粒随温度的升高快速长大。晶粒长大动力学表明：在高于d相固溶线温度以上进行固溶处理时，晶粒生长指数随着固溶温度的升高而增加；固溶处理温度为1000和1050 ℃时的晶粒长大激活能为223.849 kJ/mol，晶粒长大机制为自扩散过程控制机制，并建立了相应的晶粒长大动力学方程。

Abstract:

Grain growth behavior and its kinetics during the solution treating process of hot continuous rolled (HCR) GH4169 superalloy have been investigated. The experimental results show that the d-phase dissolution temperature of HCR GH4169 superalloy is from 990 °C to 1000 °C, and the d-phase in the superalloy greatly restrains grain growth. The solution treatment at the temperature below d-phase dissolution leads to little variation of grain size, and the solution treatment at the temperature above the d-phase dissolution leads to the rapid grain growth for HCR GH4169 superalloy. The grain growth kinetics at the temperature above the d-phase dissolution shows that grain growth exponentially increases with the increasing of solution treating temperature. At the temperatures from 1000 °C to 1050 °C, the activation energy value for grain growth in HCR GH4169 superalloy is 223.849 kJ/mol, which means that the grain growth mechanism is self-diffusion-controlling process, and the grain growth kinetics eqution are given.