Abstract: Theoretical analysis, numerical simulation and experiments of hot forming for ultra high strength boron steel are studied. The hot forming influence of boron steel is analyzed and the best temperature range 750~800 ℃ for hot forming is obtained. Then the design of the reinforced beam’s die, the cooling system and technique process are implemented by the methods of numerical simulation, optimization and experiments. The experimental results of boron steel components formed by the designed die show that the hardness value presents a homogenous distribution and the Vickers hardness is higher than 430, the yield limitation of the warm forming material is 11 000 MPa, the strength limitation is 1 430 MPa and that the martensite is homogenous. These results indicate the feasibility of the methods. Feasibility methods including theoretical analysis, numerical simulation and experiments are provided to the design of the die and manufacturing process of hot forming for vehicle components.

Key words: Boron steel, Formability, Hot forming, Numerical simulation, Theoretical analysis