| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a steel sheet excellent in strength and hydrogen embrittlement resistance characteristics after hot stamping in which press forming and hardening by contact with molds are performed in one stage, and hot-stamping formed articles excellent in the strength and the hydrogen embrittlement resistance characteristics. Ž<P>SOLUTION: The steel sheet contains, by mass%, 0.15 to 055% C, 0.010 to 0.100% Al, 0.001 to 0.040% Ti, 0.0003 to 0.0050% B and further contains Mn and Si so as to satisfy 0.005≤(Mn+Si)≤0.40%, ≤0.030% P and ≤0.020% S. The hot stamping method comprises heating the steel sheet to an Ac<SB>3</SB>transformation point and above, press forming the steel sheet without cooling the steel sheets to <Ar<SB>3</SB>transformation point, and performing hardening as it is by contact with the molds. The hot stamping formed articles are composed of the components described above and have the metal structure composed of martensite. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
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