The grain growth behavior of nickel-based superalloys is of great significance for the formulation of forging and heat treatment processes. The grain growth behavior of GH3230 alloy was studied in the temperature range of 1 150 ℃-1 240 ℃ for 1-10 hours. The effects of critical process parameters such as heating temperature and holding time, on the grain size were analyzed, and a grain growth model of GH3230 alloy was established. The results show that the grain growth of GH3230 alloy is more sensitive to the heating temperature. Grain growth accelerates rapidly with increasing temperature. When the heating temperature is higher than 1 220 ℃, abnormal grain growth occurs. The precipitation of carbides on the grain boundaries pinns the grain growth. After holding at 1 150 ℃ for 3 hours and at 1 180 ℃-1 240 ℃ for 1 hour, the original carbides on the grain boundaries gradually dissolve, and the grain growth rate increases. A grain growth model of GH3230 alloy in the heating range of 1 150 ℃-1 220 ℃ and holding time not exceeding 10 hours was established as D=D
0
+e
12.66
t
0.206
exp(-133 602/RT), and the predicted values are in good
agreement with the experimental values. The results can provide certain references for actual production and numerical simulation studies.
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