Microstructure and mechanical behavior of new type multi-layer metallic composite material in hot forming

The hot forming (quenching and forming at the same time) oxidizes and decarburizes the steel surface. The automotive components and parts formed in this technique show soft surface and hard inside. The material properties present gradient distributions in the thickness direction. The exterior hardness and strength are low, while the interior hardness and strength are high. Then the new type multi-layer metallic composite material is formed. To investigate the crashworthiness of the new metallic composite materials, the hot forming stamping pieces are experimentally and numerically studied. Taking the door reinforced beam for the samples, the three-point bending was carried out by experiment and finite element analysis (FEA). By comparing the crash force and energy absorption between the metallic composite materials and its every single phase material, it is found that the metallic composite materials have the comprehensive performance of every single phase material. So the new metallic composite material is a good alternative material in application of absorbing energy.