Structure of hardened carbon steels after plasma heating of the surface

The structure of the zone of plasma effect and the corresponding scattering of the values of the microhardness are determined by the variety of the processes of formation and decomposition of microchemically inhomogeneous austenite under the conditions when the diffusion processes have not been completed. The preservation of high-carbon microregions in the places of pearlite and high cooling rates of austenite provide martensite with a high microhardness (800-1250 H depending on the carbon content) that exceeds considerably the microhardness of martensite obtained after volume hardening.