电磁胀形管坯所受磁压力的瞬态分布  

Transient distribution of magnetic pressure in electromagnetic tube bulging

作　　者：李忠[1] 李春峰[1] 赵志衡[2] 

机构地区：[1]哈尔滨工业大学材料科学与工程学院,哈尔滨150001 [2]哈尔滨工业大学电气工程及自动化学院,哈尔滨150001

出　　处：《材料科学与工艺》2008年第3期301-305,共5页Materials Science and Technology

摘　　要：管坯所受磁压力的准确求解是电磁成形变形分析,优化成形系统工艺参数的基础.通过ANSYS/EMAG软件,用远场单元来说明磁场在远场区间的耗散问题,对电磁胀形时作用在管坯上的磁压力进行准确计算.在线圈长度一定的条件下,讨论了管坯尺寸对磁压力瞬态分布和磁场扩散的影响,并根据管坯端部径向磁压力和中部径向磁压力的比值,提出以磁压力分布不均匀系数来反映磁场不均匀分布的程度.计算结果表明:当管坯和线圈的相对长度大于1时,管坯上与线圈等高处承受轴向拉应力,磁场扩散现象不严重;当相对长度小于0.92时,管坯端部承受轴向压应力,磁场扩散现象严重,相对长度0.92时为电磁胀形均匀成形的条件.The accurate solution of magnetic pressure is the basis for analyzing the deformation and optimizing the processing parameters of forming system. The transient magnetic field analysis was carried out with ANSYS/EMAG, the far field element was used to calculate the magnetic diffusion in far field region, and transient distributions of magnetic pressure with various sizes of tubes were accurately calculated. Under the conditions of fixed coil length, the effect of tube size on transient distribution of magnetic pressure and magnetic diffusion was discussed. According to the ratio of tube length and coil length, the uneven distribution coefficient of magnetic pressure was presented to show the uneven distribution extents of magnetic field. The calculated results show that when the relative length is greater than 1, axial tension stress acts on the location equal to coil length, the magnetic diffusion is not obvious ; when it is less than 0.92, tube ends are subjected to the axial compression stress, the magnetic diffusion is serious ; when it equals 0.92, the tubes are uniformly bulged.

关 键 词：磁场耗散 电磁胀形 磁压力 相对长度 均匀成形 

分 类 号：TG391[金属学及工艺—金属压力加工]