| 摘要 |
PROBLEM TO BE SOLVED: To provide a method that can yield a press-molded product capable of achieving a balance between high strength and elongation at a high level and is useful for obtaining a press-molded product that shows good softening-prevention property at HAZ, and to provide the press-molded product exerting such characteristics.SOLUTION: A method for manufacturing a press-molded product includes: heating a steel sheet for hot pressing to a temperature equal to or higher than 900°C but equal to or lower than 1,100°C; subsequently starting press molding; while maintaining an average cooling rate of ≥20°C/sec during and after molding, cooling the steel sheet for hot pressing to a temperature equal to or lower than a temperature 100°C lower than the bainite transformation start temperature Bs but equal to or higher than the martensite transformation start temperature Ms within a die; and cooling the steel sheet for hot pressing to 200°C or lower at an average cooling rate of <20°C/sec. Here, the steel sheet for hot pressing has a prescribed chemical composition, wherein the average circle equivalent diameter of Ti-containing precipitates contained in the steel sheet having a circle equivalent diameter of ≤30 nm is ≤6 nm, and the precipitated Ti content and the total Ti content in the steel satisfy the following relation (1): precipitated Ti content (mass%)-3.4[N]<0.5×[total Ti content (mass%)-3.4[N]] (wherein [N] is the N content (mass%) in the steel). |
