高效电火花线切割磁场对表面烧伤影响研究

为减少往复走丝电火花线切割在大能量加工条件下工件表面出现的烧伤条纹,分析了烧伤条纹形成的机理:烧伤条纹主要是因汽化后切缝内工作液不足,熔融的蚀除产物无法随工作液向切缝后部顺畅地排出,从而附着在切缝侧壁而产生。而与切缝轨迹方向平行的梯度磁场可对铁基蚀除产物产生磁场力作用,以借助磁场来促进蚀除产物的排出。试验结果显示:磁场能有效减轻烧伤条纹的产生,且通过极间放电波形的采集发现,在磁场作用下放电波形中击穿延时比例增加,说明极间放电间隙状态有所改善。

Effect of Magnetic Field on Surface Burning in High-Efficiency HSWEDM

To avoid surface burning caused by high energy machining in HSWEDM, this paper explores the mechanism of burning. Dielectric which gasified largely by high energy becomes not enough to evacuate debris and cool the melt debris. Melt debris attach to the surface of gap and this is the so called burning. Magnetic field which parallel to the track of gap can improve evacuation of iron debris due to the magnetic force. The result of experiment proves that magnetic field can reduce burning apparently. The increasing proportion of waveform with ignition delay indicate that situation of inter-electrode has improved due to magnetic field.