Steel sheet with excellent bendability

摘要

A steel sheet with excellent bendability in which the main structure is composed of retained austenite (5-30 area%) and ferrite (no less than 50 area%) such that there exist no more than 40 carbide grains per 2000 mu m<2> between the retained austenite and the ferrite. The steel sheet is suitable for automobiles which exhibits bending properties (bendability and tight bendability) even though its strength is as high as 600 to 1400 MPa.