Three-dimensional Numerical Simulation and Experimental Analysis of Austenite Grain Growth Behavior in Hot Forging Processes of 300M Steel Large Components

The microstructure models were integrated into finite element (FE) code, and a three-dimensional (3D) FE analysis on the entire hot forging processes of 300M steel large components was performed to predict the distributions of effective strain, temperature field and austenite grain size. The simulated results show that the finest grains distribute in the maximum effective strain region because large strain induces the occurrence of dynamic recrystallization. However, coarse macro-grains appear in the minimum effective strain region. Then, 300M steel forging test was performed to validate the results of FE simulation, and microstructure observations and quantitative analysis were implemented. The average relative difference between the calculated and experimental austenite grain size is 7.56%, implying that the present microstructure models are reasonable and can be used to analyze the hot forging processes of 300M steel.