Research on a new type of metal composite material in hot forming and its application

A new type of metal composite material can be manufactured by controlling heating temperature and designing the layout of cooling pipes in hot forming process of ultra high strength steel. The yield strength of this type of metal material varies from 380 MPa to 1000 MPa continuously, and its strength limitation varies from 480 MPa to 1600 MPa continuously. In this new hot forming technology, boron steel named as 22MnB5 is stamped by one-step process of hot forming to obtain the metal composite material and manufacture the part consisting of the metal composite at the same time. The hot forming technology of U-shaped part consisting of the metal composite material is provided. Then the microstructure of the U-shaped metal composite material is analyzed and the tensile test is also implemented. The experimental results show the material properties have the characteristics of continuous distribution along the main direction of energy absorption during crash process, which indicates the feasibility of hot forming technology of the metal composite material. The top-hat thin-wall structure consisting of U-shaped metal composite material is employed to analyze the crashworthiness of the new type of metal composite material. By distributing the single phase material of U-shaped composite part properly, the energy absorption ability is increased by 58.7% and the crash force is decreased by 23.4%, which indicate the new type of metal composite material has the comprehensive performance of every single phase material. So the metal composite is a good alternative material in application of crash resistance.