The phase transformation model of SCM435 steel

The continuous cooling transformation (CCT) curves of SCM435 steel were measured by a thermal-physical simulator. The micro-structures at room temperature were observed by optical microscope. Data processing was carried out by utilizing Origin software. The phase model of ferrite, pearlite, bainite, and martensite were regressed on the basis of quantity of phase transformation and phase transformation under different cooling speed of SCM435 steel. The relationship models of phase transformation temperature-cooling rate and quantity of phase transformation-cooling rate were accurately established. The optimal coefficients of this steel were obtained through regressive calculations. Finally, the measured experimental data and calculated regression curves of SCM435 steel were compared. It was shown that the calculated result was consistent with experimental data, proving the rationality of the models established and the feasibility of data processing methods. So real-time response could make for real cooling rate in actual production according to the regression results, and more accurately control could be used in production.