Microstructure and mechanical property of a novel hot dip galvanized dual phase steel with high ductility

A novel hot dip galvanized dual phase steel with high ductility (DH) was designed with a novel chemical composition and hot-galvanized process. An ideal microstructure composed of ferrite, martensite, bainite and retained austenite was obtained in DH steel. Consequently, subjected to similar hot dip galvanizing process, a higher ductility was obtained in DH steel. The result indicated that retained austenite was beneficial to ductility, obvious TRIP effect of retained austenite presented during the whole tensile deformation, contributing to the strength and ductility.