Patent ID: 7572407
Filing Date: 2009-08-11
Classification: C21D,C22C

Abstract:
1. A welded vehicle structural component having a welding heat-affected zone comprising: a martensitic stainless steel sheet having superior workability comprising, on a mass basis, less than about 0.02% of carbon; about 1.0% or less of silicon; less than about 1.5% of manganese; about 0.04% or less of phosphorus; about 0.01% or less of sulfur; about 0.05% or less of aluminum; about 1.5% or more and less than about 4.0% of nickel; more than 13.0% and less than about 15% of chromium; about 0.5% to less than 1.5% of molybdenum; and less than about 0.02% of nitrogen, the balance being iron and unavoidable impurities, wherein relationships (1) to (4) are satisfied: wherein the steel sheet is 1) a cold rolled steel sheet having a thickness of 0.3-3.0 mm or 2) a hot rolled steel sheet having a thickness of 1.5-8.0 mm and generates a Charpy impact value of the welding heat-affected zone at −50° C. of 50J/cm 2 or more and a tensile strength of more than about 600 MPa.