Coated steel sheet and high-strength press-hardened steel component and method for producing same

• Main Authors: LE GUILLARD SANDRA, FILIPPO CLEMENT, SALIB MATHIEU, DUSSAUSSOIS DAVID
• Format: Patent
• Language: Chinese; English
• Published: 08.08.2023
• Subjects: CHEMISTRY; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS

The invention relates to a coated steel sheet and a press-hardened steel part having a composition comprising: C: 0.26 to 0.40 wt%, Mn: 0.5 to 1.8 wt%, Si: 0.1 to 1.25 wt%, Al: 0.01 to 0.1 wt%, Cr: 0.1 to 1.0 wt%, Ti: 0.01 to 0.1 wt%, B: 0.001 to 0.004 wt%, P: 0.020 wt%, S: 0.010 wt%, N: 0.010 wt%, and the balance being Fe and unavoidable impurities. The remainder of the composition is iron and unavoidable impurities resulting from smelting. The press-hardened steel component comprises: a body having a microstructure comprising more than 95% martensite and less than 5% bainite in surface fraction; a coating at a surface of the steel component; a ferritic interdiffusion layer between the coating and the body, and a ratio between a ferritic grain width GW interdiffusion layer in the interdiffusion layer and a primal austenitic grain size PAGS body in the body satisfy the following equation (GW interdiffusion layer/PAGS body)-1 > = 30%. 本发明涉及经涂覆的钢板和压制硬化钢部件，其具有包含以下的组成：C：0.26重量％至0.40重量％，Mn：0.5重量％至1.8重量％，Si：0.1重量％至