Development of CFRP members for absorbing impact energy and evaluation of their mechanical properties

随着人们对汽车轻量化和乘客安全的兴趣的增加，碳纤维增强塑料（CFRP）受到高度关注，因为它有助于汽车的轻量化，从而解决环境问题，如减少汽车尾气排放。为了保证碰撞安全性，必须对碳纤维复合材料汽车构件进行开发，明确其力学性能。通过本课题的研究，根据课题的目的，得出以下几点结论。(1)为了吸收汽车侧面碰撞时的冲击能量，可以使用冲击梁，其常规类型是钢制的。研制出了重量更轻、抗拉强度更高的CFRP带代替钢冲击梁。给出了CFRP薄带在冲击载荷作用下的试验和数值结果。结果吻合较好，表明CFRP薄带代替钢质冲击梁的可能性较大。(2)采用有限元法对不同截面的碳纤维复合材料钢瓶进行了正面碰撞时有效吸收冲击能的冲击响应分析，明确了碳纤维复合材料钢瓶吸收冲击能的能力。(3)采用有限元法对CFRP与金属（钢或铝）混合复合材料的冲击吸能性能进行了研究，数值计算结果与实验结果在允许误差范围内吻合较好

With an increase of the interest in the lightening of the automobile and of the safety to the passenger, CFRP is highly noticed due to contribute a lightweight of automobiles, which leads to solve environmental problems, such as a reduction of exhaust gas in the automobiles. In order to establish a collision safety, a development of CFRP automobile members should be performed and their mechanical properties must be made clear. Through the research project, the following items are obtained according to the aim of project.(1)In order to absorb impact energy in a side collision of automobiles, an impact beam is useful and its conventional type is made of steel. CFRP belts having lighter weight and higher tensile strength are developed for substituting steel impact beams. The experimental and numerical results of CFRP thin belts under the impact loads are shown. Their results agree well each other and show a higher possibility of CFRP thin belt instead of the steel impact beams.(2)Impact response analyses of CFRP cylinders having various kinds of cross section are performed by the FEM for efficiently absorbing impact energy in the case of front collision and an absorbing ability of impact energy in the CFRP cylinders are also made clear by the FEM.(3)Hybrid composites composed of CFRP and metal (Steel or Aluminum) which are expected to increase impact energy absorption are examined by the FEM and their numerical results by the FEM show the good accordance to the experimental ones within the allowable margin of error