Numerical Simulation Of Recrystallization And Grain Growth Of Metal Hot Forging Process

In the past twenty years, with the development of computer technology and numerical calculating methods, numerical simulation technology based on finite element method(FEM) has already become a powerful tool for researching plastic deformation. Significant progress has been made for study on metal hot plastic deformation and precise prediction of the distributions of varied deforming fields. At present, study on hot plastic deformation has been no more limited to the distributions of metal macro plastic flow behaviors and partial thermal-kinetic parameters, rather than interior microstructure evolution. The requirements on high quality, efficiency and low consumption in manufacturing forging parts are satisfied by optimizing deformation technology and process parameters according to microstructures and mechanical properties. So predicting microstructure evolution during metal plastic deformation by means of computer simulation technology has being played a very important role in promoting the development of advanced plastic processes.Secondary user subroutines DEF_USR have been developed and embedded in commercial forming simulation software DEFORM-TM by means of Absoft Fortran, which has managed to predict microstructure evolution during metal (C-Mn steel) hot forging process. The main research works include implementing metal material constitutive laws considering dynamic, static, metadynamic recrystallization and grain growth into DEFORM during hot deformation, interpass time and holding time, which has successfully predicted microstructure evolution in DEFORM-TM. Two examples, square billet upsetting and rear flange axle forging, have been simulated and compared with published results. It indicates that the secondary user subroutines developed in this paper are validated. Consequently, a reliable universal simulation module is provided to simulate technical processes and predict microstructure evolution during metal(C-Mn steel) hot plastic deformation. The results have also revalidated that the effects of grain size on material mechanical properties are important. The distributions of grain size are dependent on deformation extent, strain rates, deformation temperature, holding time, interpass time between multi-process, metal stacking fault energy, chemical constituents and original...