비대칭 모자형 사각관의 정적 및 동적 압궤실험을 통한 충돌성능 평가

Abstract

The axial crush of channeled members is important in estimation of the energy absorption during the car frontal crash. In order to improve the energy absorption capacity and the velocity deceleration factor of an auto-body, the front-side members are mounted at the side of the engine room and made undergo the axial crush at the beginning of the car crash. There have been so many studies about square or rectangular boxes and hat-type specimens for the axial crush both experimentally and analytically while there are few studies about asymmetric hat-type specimens that are used for designated deformation. The axial crush of asymmetric hat-type specimens is, however, difficult to describe analytically with the kinematic crush mechanism. In this paper, asymmetric hat-type specimens are fabricated by spot welding or laser welding with different spacing between two welded spots. The specimens are then deformed for the axial crush at the various crush velocity. The experimental result shows that the specimens are not deformed in a consistent manner, but arbitrarily. In this type of axial crush, the length of the flange region is an important parameter as well as the spacing between welded spots. Experimental results also show the difference in the crush mode between the spot-welded specimens and the laser-welded ones. The difference in the first peak and average load is also demonstrated as well as the energy absorption capacity.