To provide a front side member having a bending work part bending two-dimensionally or three-dimensionally, and having ultrahigh strength with tensile strength >1,100 MPa.
In this front side member 53, a partial part of a tip part 54a is a non-quenching part without performing a quenching process thereto; residual parts excluding the partial part of the tip part 54a are high-frequency quenching parts to which a high-frequency quenching process has been performed; the whole of an inclined part is a high-frequency quenching part to which a high-frequency quenching process has been performed; a partial part of a rear end 54b is a non-quenching part without performing a quenching process thereto; and residual parts excluding the partial part of the rear end 54b are high-frequency quenching parts to which a high-frequency quenching process has been performed thereto.
TOMIZAWA ATSUSHI
SHIMADA NAOAKI
KOJIMA HIROTATSU
| JP2004323967A | 2004-11-18 | |||
| JPS58105881A | 1983-06-23 | |||
| JP2004114912A | 2004-04-15 | |||
| JP2003048567A | 2003-02-18 |
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