A New Type of Multi-layer Metal Composite Materials for Preventing Impact and Absorbing Energy in Hot Forming and its Application

Hot forming (quenching and forming at the same time) makes the steel surface oxidation and decarburization. Stamping parts formed in this technique shows low hardness in the exterior and high hardness in the interior. The material properties exhibit the continuous functionally gradient distribution in the thickness direction. The exterior hardness and strength is low, while the interior hardness and strength is high. So, the new type of multi-layer metal composite materials is formed. The microstructure, hardness, strength and plasticity of this new metal composite material is analyzed and taking the reinforced beam for example, the three-point bending experiment is implemented. To investigate the crashworthiness of the new metal composite materials, the finite element analysis (FEA) model of the reinforced beam is established on the basis of the metallographic and three-point bending experiments. To compare the crash force and energy absorption between the metal composite materials and each phase material in the interior, it is found that the metal composite materials have the comprehensive performance of every single-phase material. So, it is a good alternative material in application of bearing impact and absorbing energy.