High-strength cold-rolled steel sheet or high-strength hot-dip galvanized steel sheet having a tensile strength of 980 MPa or more and a 0.2% yield strength of less than 700 MPa, which is excellent in ductility, stretch flangeability, and weldability.

摘要

To provide a high-strength cold-rolled steel sheet having excellent ductility and stretch-flangeability as well as weldability in a range in which a tensile strength is 980 MPa or higher and a 0.2% yield strength is less than 700 MPa (preferably 500 MPa or higher).SOLUTION: A high-strength cold-rolled steel sheet contains, as its chemical component composition, in mass%, C: 0.07-0.15%, Si: 1.1-1.6%, Mn: 2.0-2.8%, P: more than 0% to 0.015% or less, S: more than 0% to 0.005% or less, Al: 0.015-0.06%, Ti: 0.010-0.03%, and B: 0.0010-0.004% with the balance being iron and unavoidable impurities.SELECTED DRAWING: None