| 摘要 |
PROBLEM TO BE SOLVED: To provide a reinforcing member for an automobile, having high bending reaction force at the initial stage of collision and also having a sectional form to reduce the manufacturing cost and the weight. SOLUTION: This reinforcing member for an automobile is a square steel pipe having a square section, satisfying the following expressions (1) to (3) and having strength such as tensile strength of 690 MPa or more. The expression (1) is R<SB>1</SB>≤1.5t, the expression (2) is t<SB>R</SB>≥1.1t, and R<SB>1</SB>≥R<SB>2</SB>, wherein t is the board thickness (mm) of a side, t<SB>R</SB>is the board thickness of the corner, R<SB>1</SB>is an outside corner (mm), and R<SB>2</SB>is an inner corner R(mm). Further, preferably the maximum value and the minimum value of hardness in the section of the square steel pipe are both in the range of±30% of the average value in the whole section. COPYRIGHT: (C)2005,JPO&NCIPI |
