| 摘要 |
<p>This hot-stamped steel material comprises a chemical composition including, in mass%, 0.18-0.26% of C, more than 0.02% to 0.05% or less of Si, 1.0-1.5% of Mn, 0.03% or less of P, 0.02% or less of S, 0.001-0.5% of Al, 0.1% or less of N, 0.001-0.02% of O, 0-2.0% of Cr, 0-1.0% of Mo, 0-0.5% of V, 0-0.5% of W, 0-5.0% of Ni, 0-0.01% of B, 0-0.5% of Ti, 0-0.5% of Nb, 0-1.0% of Cu, and Fe and impurities as the remainder, and is characterized in that: the concentration of Mn-containing inclusions is 0.010 mass% or more to less than 0.25 mass%; and the percentage, by number, of Mn oxides in said inclusions with a maximum length of 1.0-4.0 µm is 10.0% or more. This hot-stamped steel material ensures excellent resistance to hydrogen embrittlement even in cases where the steel material after having been hot-stamped is subjected to processing in which stress remains, such as perforation, and the steel material can also be worked easily.</p> |
