Cylindrical Shell Shaped Crash Box Using Carbon Fiber Reinforced Plastic

The front of a vehicle has a crash box that maintains the shape of the front side member and crashes ahead of the front side member. Therefore, the crash box needs to be designed to have enough strength to absorb the impact energy. However, if the crash box is too strength, the front side member crashes instead of the crash box. Carbon fiber reinforced plastic (CFRP) has a high specific strength and specific rigidity. The CFRP can change the strength and rigidity by changing the number of prepreg layers or the direction of carbon fiber in the prepreg. This report focused on the direction of carbon fiber in the prepreg. We used a uni-direction Carbon fiber prepreg and manufactured shell-shaped CFRP specimens. The directions of carbon fiber in manufactured specimens were different from each other. Drop weight tests were performed to crush these specimens and investigate the effect of the fiber direction in CFRP specimen on impact absorption performance. From these results, the increase of prepreg continuing closer to the axial direction reduces the crush amount.