Structure formation on cooling and heating steel type 25-20

Carbon and titanium effect on the mechanism and kinetics of phase transformations under cooling and heating of the Kh23N18 steel was investigated. It is found experimentally that melts are crystallized as j-dendrites with direct liquation by chromium and nickel. Growth of carbon concentration and reduction of titanium content in the steel increase dispersion of high-chromium phase, while increase of temperature and duration of heat treatment results in particle coagulation. The conducted investigations permit to simulate a scheme of structure formation under crystallization, cooling and heating of Kh23N18 steel and to develop recommendations to remove embrittlement conditioned by σ-phase precipitation