单脉冲电磁成形中洛伦兹力在时间上的双向竞争关系及其对成形效果的影响

The Two-Way Competitive Relationship of Lorentz Force in Time in Single Pulse Electromagnetic Forming and Its Influence on Forming Effect

电磁成形技术是一种利用洛伦兹力驱动金属材料发生高速变形的先进制造技术。与传统静态成形工艺相比,电磁成形因其极高的应变速率能显著地改善轻质合金材料的成形性能。同时,相比传统机械力或液压力,电磁成形所利用的洛伦兹力能够在时间和空间上灵活调控,因而具备更丰富的工艺潜能。然而,现有研究多将重点放在金属工件的成形方式及效果上,对其最主要部分——洛伦兹力,在电磁成形过程中随时间的变化过程及复杂的竞争关系并未系统分析。因此,该文针对典型的单脉冲电磁成形过程,细化电磁成形过程中各个物理量之间的动态变化关系,研究了成形过程中随时间变化洛伦兹力在铝合金板件上的竞争关系及对成形效果的影响,阐明了随时间变化的洛伦兹力的竞争关系,对所呈现成形效果的影响及原因进行了分析,更加深刻全面地理解电磁成形技术过程。

Electromagnetic forming technology is an advanced manufacturing technology that uses Lorentz force to drive high-speed deformation of metal materials.Compared with the traditional static forming process,electromagnetic forming can significantly improve the forming performance of light alloy materials due to its extremely high strain rate.At the same time,compared with the traditional mechanical force or hydraulic pressure,the Lorentz force used in electromagnetic forming can be flexibly adjusted in time and space,so it has richer process potential.However,the existing research mostly focuses on the forming method and effect of metal workpieces,and the most important part,the Lorentz force and the complex competitive relationship have not been systematically analyzed.Therefore,this paper focuses on the typical single-pulse electromagnetic forming process,refines the dynamic relationship between the various physical quantities in the electromagnetic forming process,and studies the competitive relationship of the time-varying Lorentz force on the aluminum alloy plate during the forming process and its influence on the forming process.The competitive relationship of the Lorentz force that changes with time is clarified,the influence on the forming effect is analyzed,and the electromagnetic forming technology process can be comprehensively understood.