Fem Simulation And Predication Of Grain Size In Roughing Roll For Bar Steel

Analyzing phenomena of steel rolling using numerical simulation and physical metallurgy, makes the simulation of plastic forming process possible objectively and controllably, including: regularities of distribution and metal flow of stress, strain and temperature for workpiece and dies; microstructure evolution in different stage of hot forming; research reports of dynamic recrystallization, static recrystallization and grain growth have been finished. Disclosuring the essence and relation of influence parameters, optimize technological process, promote development of manufacturing technique. The data of relation of true stress and true strain have been measured in GLEEBLE3500 machine for 40Cr workpiece in different roll temperature. Physical simulations for dynamic recrystallization and static recrystallization also have been finished. Average grain size after recrystallizatin was measured in microscopic test. Peak strain modle, dynamic recrystallization modle and static recrystallization modle have been established using data regression analysis. According to the technological data, rolling processes of steel 40Cr was simulated by DEFORM finite element software. Stress field, strain field and temperature field in the rolling process were analysied; Based on the tests results on the thermo-simulation machine, microstructure evolution models of steel 40Cr were used to calculate grain size. Microstructure evolution was simulated by the software. Quantitative description of relations about microstructure and parameters was discussed.