Microstructures and mechanical properties of 7Mn multiphase steels

摘要

Material design concept based on deformation mechanism of a composite material was recently proposed for the development of the 3rd generation AHSS1) for automotive application, which was summarized as an incorporation of microstructures increasing strength and enhancing strain hardening, and utilizing strain induced martensitic transformation of the retained austenite. The present study aims at improving mechanical property of the low carbon MnSiAl multiphase TRIP-aided steels. The approach of the present study is three folds; (1) employment of reversion of martensite, (2) addition of manganese for the purpose of increasing fraction and stability of retained austenite and hardenability as well, and finally (3) utilizing effect of grain refinement associated with a reversion transformation.