Study On Energy Absorption Characteristics Of Metal/composite Hybrid Structures

Many researches have been done that composite structures have excellent characteristics of energy absorption under transversal and axial compression conditions.However,composite materials have many problems such as high brittleness and unstable failure modes and high cost.Especially when transversal loading is applied,the composite structures are too early to lose its bearing capacity,so as energy absorption structures,the advantages of composites are not so prominent.Therefore,more and more researches have been done to hybrid structures consisted of the metal and the composite.Due to the participation of metal,the toughness of the whole hybrid structures is well maintained,and the deformation of the composite becomes more stable and regular under the regular plastic deformation of the metal.The interaction between the metal and the composite improves the energy absorption potential of the whole structure.At the same time,the cost of the whole structure can be greatly reduced as the cost of the metal is much lower than that of the com posite,so that it is better used in engineering.In this paper,the energy absorption characteristics of metal aluminum alloy and carbon fiber reinforced polymer(CFRP)hybrid structure are studied.In order to simplify the study of energy absorption char acteristics of vehicle side and positive collision,the three point bending and axial crushing experiment s are used to replace the working conditions of the side and positive collision respectively and the composite and the metal tubes are put together to replace the hybrid structure beam.Through the analysis and research of experiments,it is determined that the I type hybrid tube in three-point bending tests and the I type sandwich tube in axial crushing tests are better energy absorbing structures.In order to explore the better energy absorption characteristics of the hybrid tube as a energy absorption component in the engineering application,the parameter analysis of the length and thickness of the CFRP tube in the hybrid tube is done by the finite element simulation,and the influence of the different parameters on the energy absorption characteristics of the whole hybrid structure is qualitatively studied.Finally,in the sake to make the whole research more meaningful on engineering application,the hybrid structure is applied to the automobile bumper.And the characteristics of the intrusion,energy absorption and maximum acceleration of the hybrid bumper are studied under low speed impact.According to the numerical model of the bumper,researches are done in finite element analysis(FEA).Meanwhile,advantages of the hybrid bumper are qualitatively analyzed under low speed impact,thus providing the basic ideas and methods for the engineering design.