| 摘要 |
PROBLEM TO BE SOLVED: To provide a vehicular bumper reinforcement comprising an aluminum alloy extrusion-molded hollow material and continuously changing the cross-sectional shape to a different one in a longitudinal direction.SOLUTION: A hollow cross-sectional shape of a vehicular bumper reinforcement 1 comprising an aluminum alloy extrusion-molded material changes continuously from the square-shaped cross sections of both ends 1c in a longitudinal direction to a nearly B-shaped cross section of a center 1b in the same direction, and the change of the hollow cross-sectional shape deforms sequentially a backside flange 3 having the thickness different portions and upper and lower webs 2 and 2' in the hollow cross section over the longitudinal direction. The structure of the vehicular bumper reinforcement comprises bringing the hollow cross-sectional shape close to a collision surface side flange 4 gradually while changing the hollow cross-sectional shape and the width of a vehicle longitudinal direction. |
