Mechanical Properties and Structure of a VNS9-Sh Steel as Functions of the Tempering Temperature

Abstract

The influence of the tempering temperature in the range 125–700°C on the structure and mechanical properties of an austenitic–martensitic VNS9-Sh (23Kh15N5AM3-Sh) sheet TRIP steel is studied. A stable high level of the mechanical properties of the steel is found to be retained up to a tempering temperature of 450°C. At higher tempering temperatures, the mechanical properties decrease sharply against the background of the reverse transformation of strain-induced martensite into austenite. After tempering at 650°C and furnace cooling, the structure of the steel consists of α ferrite.