| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a manufacturing method for a vehicle body side part structure in which degree-of-freedom of spot weld portions can be increased.SOLUTION: Steel materials 1a, 1b, 1c are cut into a predetermined planar shape by use of presses 2a, 2b, 2c thereby forming an upper member 3a, a reinforcement member 3b and a lower member 3c. A carbon content of the steel material 1c is so set as to be smaller than that of the steel materials 1a, 1b. Next, the upper member 3a, the reinforcement member 3b and the lower member 3c are integrated. The reinforcement member 3b is laminated on the upper member 3a. Further, the upper member 3a and the lower member 3c are partially laminated. Then, the laminated portions of the upper member 3a and the reinforcement member 3b, and the laminated portions 6 of the upper member 3a and the lower member 3c are respectively spot-weld thereby joining the members to each other to form a blank. Thereafter, the spot-weld blank is heated to a temperature higher than a transformation point, and the blank is hot press-molded by one press 4.</p> |
