Effects of Initial Rolling Temperature on Rolling Deformation and Microstructure Evolution of 42CrMo Casting Ring Blank

摘要

It is the basis for the new casting-rolling compound forming technology to investigate the rules of rolling deformation and microstructure evolution of casting ring blank. The initial rolling temperature of casting ring blank is one of the key factors influencing deformation and dynamic recrystallization behavior. In this paper, dynamic recrystallization models of as-cast 42CrMo steel were derived from thermo-simulation experimental results. Then, under DEF0RM-3D software environment, deformation and dynamic recrystallization of 42CrMo casting ring blank were simulated at different initial rolling temperature by coupled thermo-mechanical finite element method. According to the simulation results, the effects of initial rolling temperature on strain fields distribution and dynamic recrystallization of 42CrMo casting ring blank were discussed. The results show that: (1) increased initial rolling temperature makes plastic deformation expand from ring's outer and inner-layer to middle and distribute ever more evenly; (2) increased initial rolling temperature can lead to increased dynamic recrystallization fraction, but grain size of ring's inner and outer-layer becomes smaller and smaller, while that of mid-layer coarser and coarser.