关键词: 板材成形, 电控永磁, 磁流变弹性体, 压边力控制

Abstract: When deep drawing sheets of varying thicknesses, different blank holder gaps were formed. In the traditional electrically controlled permanent magnet blank holding processes, the medium in the blank holder gaps was air, which created a magnetic circuit air gap during magnetic loading, leading to magnetic losses. A design for MRE was proposed as a magnetic medium to fill the blank holder gaps, creating an electrically controlled permanent magnet blank holding method without magnetic circuit air gaps, thereby reducing magnetic losses. A blank holding force loading structure with 36 magnetic pole units was designed, and finite element simulations were conducted under different blank holder gaps and varying magnetic loading levels to analyze the change in crimping forces with the addition of MREs on the blank holding force, followed by experimental validation. The results show that the addition of MREs may effectively enhance the blank holding forces with a more significant improvement as the blank holder gap increases, and the inclusion of MREs does not affect the distribution of the blank holding forces in the sheet blank holding areas. Deep drawing experiments were conducted using cylindrical parts as the experimental subjects, verifying that the new processing method is entirely feasible. 

Key words: sheet metal forming, electro-permanent magnet(EPM), magnetorheological elastomer(MRE), blank holder force control