Structural-Phase Transitions in Cold-Resistant Low-Carbon Martensitic Steels Susceptible to Structural Heredity

Abstract

An approach proposed to creating steels with a new combination of mechanical properties and a high impact toughness at low temperatures. This approach is based on the phenomenon of structural heredity and consists in the formation of a two-phase martensite–martensite structure and the designing of a carbide subsystem. A grain size distribution is found, and the possibility of two-stage formation of low-carbon austenite is shown. A martensitic transformation model, which takes into account the grain size distribution, is developed and experimentally tested. The models are tested on low-carbon Cr–Mn–Ni–Mo–V–Nb martensitic steels.