The Experimental Research On Electromagnetic Forming Of High Strength Steel Sheet

With the development of automotive industry, several major problems which the automobile concerned are energy saving, safety and service performance. The lightweight of automobile can reduce the energy consumption and emissions effectively, and the application of high strength materials can improve the safety of the automobile body. Currently, the main high strength material of the automobile body is high strength steel. Reducing the thickness of high strength steel stamping parts will not have great influence to the quality of stamping parts. The automobile body will have sufficient strength and stiffness by using high strength steel to loss weight. However, the yield and tensile strength of high strength steel are great. During the forming process, the high strength steel will present easier rupture and greater springback than the ordinary steel, and the stability of the size and shape will be worse. Therefore, the research of high-strength steel forming technology is the main way to improve its formability and expand its application.Electromagnetic forming is one kind of high velocity forming, which release energy in a short time and make the metal forming with impulse impact pressure. Compared to the conventional forming, the formability of materials and the strain distribution on the sheet can greatly improved.In this paper, the research objects are deep drawing steel B170P1 and bake hardening steel B180H1 that produced by Shanghai Baoshan General Iron and Steel Works. First the stamping forming parameters were obtained by the quasi-static tensile experiments, then the quasi-static FLD (Forming Limit diagram) were got by quasi-static tensile test with different width of the plate and Erichsen experiments; The dates of the deformation height were obtained through the electromagnetic forming experiments, then the impact of the thickness of driving disk, the discharge voltage and the discharge capacity were analyzed. And the strain distribution of the uniform deformation stage was compared under the quasi-static condition the electromagnetic forming condition.In the simulation of electromagnetic field, the magnitude of current were compared under different parameters through the circuit's simulation; then the 3D finite element model of the double spiral flat coil was established. The distributions of inductive current, electromagnetic field intensity, electromagnetic force on the sheet were obtained.