The Study Of High-Strength Steel Rectangular Box Deep Drawing Based On Numerical Simulation

In recent years, as the development of China’s automobile industry is turning to the green, environmental protection, safety and high-performance, more and more people are paying close attention to the lightweight body of cars. Using high-strength steel not only can reduce body mass of cars and achieve the lightweight body, but also can improve the safety performance of cars by its high strength. So, high-strength steel has been used more and more widely in the field of modern automobile manufacturing. However, due to a higher yield strength of high-strength steel compared to ordinary low-carbon steel, the forming load is increased significantly, which makes the force condition of stamping mold worse. Therefore, the elastic deformation of mold has become an indispensable condition of the research for sheet metal forming.The forming process of rectangular box deep drawing is simulated by the finite element analysis software ABAQUS in this thesis. Wrinkle and crack are regarded as the evaluation criteria of deep drawing quality. Wrinkle and crack of the sheet metal are determined by the maximum thickness reduction rate and the clearance between blank holder and die, which verify the rationality of the deep drawing program. Taking die as the main object of study, we obtain the variation rule of the force for mold during deep drawing. We also investigate the sheet’s and the die’s performance rule of the rectangular box deep drawing for five different process parameters, which are die gap, die radius, punch radius, friction coefficient and BHF.We make an orthogonal experimental design, which is taken the maximum thickness reduction rate and the clearance between blank holder and die as test indexs and die clearance Z, die radius rd, punch radius rp, friction coefficient μ and BHF FY as factors affecting rectangular deep drawing performance.Under different experimental conditions for rectangular deep drawing in the orthogonal table, We make numerical simulation experiment based on ABAQUS. With comparison to the range, the order of influence of rectangular box deep drawing is μ>rp>FY>Z>rd under the index of the maximum thickness reduction rate; the order of influence of rectangular box deep drawing is rd>rp>Z>FY>μ under the index of the clearance between blank holder and die. The simulation results are analyzed by using the comprehensive balance method and we obtain an optimal process parameters’combination of rectangular box deep drawing forming when the mold gap Z is1.1mm, die radius rd is9mm, punch radius rp is8mm, the friction coefficient μ is0.1, BHF FY is600KN.