A dual-coil electromagnetic forming (EMF) method assisted by radial Lorentz force was proposed herein to achieve the die forming of deep-cavity sheet metal parts. The objective of this study was to certify the extent to which the formability and forming accuracy can be improved by the proposed method. For comparative study, a single-coil EMF system without radial Lorentz force was also utilized. To develop the deformation process, the experiments and simulations of deep-cavity aluminum workpieces under a wide range of voltage combinations were conducted by the single-coil and dual-coil EMF, respectively. The experimental results showed that the dual-coil EMF resulted in the formation of the deep-cavity workpiece with high forming accuracy, maximum die-fitting gap of 0.35 mm, and more uniform thickness distribution. In contrast, the workpiece tended to crack without contacting the die by the single-coil EMF. Based on the simulation results, dynamic deformation behaviors of the deep-cavity workpieces were demonstrated and the underlying mechanisms of the improved formability and forming accuracy were explained. Moreover, the process window of die-fitting gap control indicated that the fittability could be controlled by adjusting the voltage combinations of the dual-coil EMF, and the corresponding optimum voltage of Coil-2 (V₂) that contributed to high forming accuracy decreased with the increase of the voltage of Coil-1 (V₁). Therefore, the proposed dual-coil EMF exhibits more flexibility and efficiency for producing the deep-cavity sheet metal part with a higher forming accuracy than the single-coil EMF, extending the potential application of the conventional EMF due to the utilization of multiple coils.

本文提出了一种利用径向洛伦兹力辅助的双线圈电磁成型（EMF）方法来实现深腔金属板零件的模具成型。这项研究的目的是证明所提出的方法可以在多大程度上改善可成形性和成形精度。为了进行比较研究，还使用了没有径向洛伦兹力的单线圈EMF系统。为了开发变形过程，分别通过单线圈和双线圈电动势进行了深腔铝工件在多种电压组合下的实验和模拟。实验结果表明，双线圈电动势可形成深腔工件，成型精度高，最大模具装配间隙为0.35 mm，厚度分布更均匀。相反，单线圈EMF会使工件易于破裂而不接触模具。基于仿真结果，论证了深腔工件的动态变形行为，并解释了改善可成形性和成形精度的潜在机理。此外，压铸间隙控制的过程窗口表明，可通过调节双线圈EMF的电压组合和相应的线圈2最佳电压（V₂）的高成形精度随着线圈1（V ₁）的电压上升而降低。因此，所提出的双线圈EMF比单线圈EMF具有更大的灵活性和效率，以更高的成形精度来生产深腔金属薄板零件，由于利用了多个线圈而扩展了常规EMF的潜在应用。