Temperature and deformation effect on structural changes in thermomecanically treated austenite

Investigation into thermal and mechanical stability of hot-deformed austenite substructure in 60N20 steel is conducted. The samples have been deformed by rolling at 800, 900 and 1020 deg C. Tensile and stress relaxation tests have been conducted at 300, 400 and 500 deg C. States differing by prevailing type of substructure: typical for hot strain hardening polygonization and recrystallization, are obtained as a result of different regimes of treatment. Material subjected to structural strengthening conditioned by polygonization is stated to have high relaxation stability at all test temperatures