磁场辅助电解加工装置的磁场设计和试验

Design of Device and Experiment on Magnetic Field Assisted Electrochemical Machining

为改善电解加工间隙流场,针对型面和型孔电解加工,设计在夹具体内镶嵌磁路、在阴极体侧镶贴永磁体的电解加工装置。进行有限元分析和试验,确定型面加工采用内封闭多体渐变磁路的结构。试验结果,用3坐标测量仪对加工的曲面尺寸进行测量,曲面形状偏差小于0.05mm,用轮廓仪测得表面粗糙度为Ra0.2μm。型孔加工采用N、S相间排布的磁路,可有效消除加工后的侧壁流纹,表面粗糙度为Ra0.8μm。与不加磁场相比,复制精度和表面粗糙度均显著提高的原因是磁力线切割流线,洛仑兹力起到消除束流的作用。

To improve flow field in the gap of electrochemical machining（ECM）, a series of ECM devices are designed with magnetic circuit embedded inside the clamp lining and permanent magnet inlaid on the cathode sidewaU for electrolytic shaping and machining shaped-hole respectively. Finite element analysis （FEA） is applied and experiments are carried out. The configuration with the multi-body gradually changing magnetic circuit is ascertained for electrolytic shaping. The experiments demonstrate that machining results are improved significantly with the shape error of the curved surface less than 0.05 mm, the surface roughness Ra 0.2 μm. When magnetic circuit with N, S alternately arranged is inlaid on cathode the endlong veins on the sidewall of shaped-hole are decreased effectively and the specimen surface roughness is Ra 0.8 μm. The magnetic field is applied in the direction that magnetic flux could perpendicularly cut flow streamline, so that Lorentz force is conducive to the spreading out of the flow beam, thus improving the surface roughness and the accuracy markedly.