HIGH TENSILE STRENGTH STEEL SHEET WITH EXCELLENT WORKABILITY

摘要

PROBLEM TO BE SOLVED: To provide a high tensile strength steel sheet combining excellent elongation with excellent stretch-flange formability both as indices to workability. SOLUTION: The steel sheet has a structure which is composed essentially of ferrite single-phase structure and in which precipitates containing V and Mo in the amounts within the range satisfying Mo/(V+Mo)>=0.25 by atomic % are dispersedly precipitated. Further, this steel sheet has >=590 MPa tensile strength.