Influence of Heat Treatment Parameters on the Non-Isothermal Transformation of AISI420 Martensitic Stainless Steel

To use steels require the correct selection heat treatment parameters in industreial applications. In martensitic stainless steels, carbides dissolution process in continuous heating and their precipitation in continuous cooling play a main role in their properties.In this study, at different temperatures and cooling rates, the thermal cycles were used on the AISI420 steel by dilatometery technique. The dilatometery results with microscopic investigations showed that the lower austenite grains size and muchconcentration alloying elements in austenite before and after dissolution of carbides, respectively, are parameters that caused alterations of martensite start temperatures (MS) in different austenitization temperature. Beside, precipitation of carbides decreaseswith increasing austenitization temperature and cooling rates under continuous cooling.