基于有限元的铁磁物质电阻点焊磁场分布分析

根据电阻点焊机构电流回路特点,利用ANSYS软件建立了铁磁性物质电阻点焊时磁场计算的有限元模型,计算了点焊过程中电流密度分布电场分布与磁感应强度分布,并采集了点焊过程中工件周围的磁感应强度,与模拟结果相比,验证模型的可靠性.结果表明,电流密度、电场强度与磁感应强度均在工件内达到最大.在铁磁性工件内部最大磁感应强度达到7 T,说明铁磁物质的磁化磁场在熔核形成、生长过程中的作用不应忽视.验证试验的测量值与计算值吻合良好,表明文中建立的有限元模型是可靠的.

Magnetic field distributionof ferromagnetic workpieces resistance spot welding based on finite element method

The magnetic field distribution during resistance spot welding(RSW) will affect the magnetic force acting on nugget and therefore, influence the nugget formation. At the same time, the magnetic field distribution also affects the electromagnetic environment, which influences the assessment of electromagnetic field exposure safety. This paper builds a finite element model of RSW according to the circuit of spot welding power source. The magnetic field during RSW of ferromagnetic workpieces was calculated, and experiments were carried out to verify the simulation. The results show that the maximum magnetic induction density was up to 7 T in the ferromagnetic workpiece. This indicates that the magnetization of ferromagnetic workpieces plays an important role in the nugget formation as well as its growth and it should not be ignored. The measured and calculated magnetic induction density agrees well, which verified the reliability of the finite element model.