METHOD OF THERMOMECHANICAL TREATMENT OF METASTABLE AUSTENITIC STEEL Russian patent published in 2016 - IPC C21D8/00 C21D6/04 C21D6/00 C21D7/13 

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy and can be used for making, for example, high-loaded parts in machine building. To produce sub micro crystalline structure in steel the method includes heating a sheet of steel 08X18H10T to the temperature of 1,100 °C, holding for 1 hour, cooling in water, cold treatment in liquid nitrogen, rolling in several passes with the total logarithmic deformation degree of e=0.1-0.2 with cooling in liquid nitrogen between those passes to form the martensite of deformation with the volume ratio of 55-75 %, then hot deformation at 400-700 °C in one or several passes with the degree of logarithmic deformation of e≤0.5 and annealing of the duration from 200 sec to 1 h within the temperature range of 600-800 °C to provide forming the sub micro crystalline structure containing austenite of up to 95 %.

EFFECT: obtained structure has high strength properties at maintaining sufficient plasticity margin.

1 cl, 1 tbl, 1 dwg, 2 ex