Effects of Test Temperature and Strain Rate on the Mechanical Properties in an Intercritically Heat-Treated Bainite-Transformed Steel

摘要

Larger amount of austenite could be retained in an intercritically heat-treated bainite-transfonned steel. The elongation and the strength-ductility balance of the steel could be enhanced considerably due to strain-induced martensite transformation and transformation-induced plasticity (TRIP) of retained austenite. The effects of test temperature and strain rate on the mechanical properties and strain induced transformation behavior of retained austenite in the steel were investigated. Total elongation and strength-ductility balance of the specimen reached maximum when it strained at a strain rate of 2.8x10~(-4)s~(-1) and at 3501. The relation between test temperature and tensile properties showed the same tendency at three kinds of strain rates. Flow stress increased considerably with decreasing the strain rate.