NUMERICAL SIMULATION OF STRUCTURAL TRANSFORMATIONS IN HYPOEUTECTOID LOW-ALLOY STEELS

Numerical simulation of the kinetics of ferritic and pearlitic transformations due to arbitrary cooling of low-alloy hypoeutectoid steels is performed. The initial data for the computations are isothermal and thermokinetic diagrams of decomposition of supercooled austenite of the studied steels. The temperatures of the start and end of pearlitic transformation due to continuous cooling are computed using the isothermal diagrams for steels 35Kh, 35KhM and 12Kh2N2. The results are used to plot thermokinetic diagrams of decomposition of supercooled austenite. For steels 15KhF, 20KhM, 25KhGF, 12Kh2N2, and 50KhF the location of the line of the end of ferritic transformation is determined using the method of successive approximations by inverse computation of the thermokinetic diagrams of decomposition of supercooled austenite into "ideal" isothermal diagrams. This makes it possible to compute the amount of the formed ferrite for the chosen thermal trajectories of cooling. The model is checked experimentally for the case of end quenching of a test piece of steel 40Kh.