叶缘曲面电火花加工的电极损耗补偿方法

Electrode Wear Compensation Method in Envelope Blade Edge of EDM

电火花成形加工依靠电极成形曲面及其相应的运动轨迹,可加工出复杂曲面。采用该方法修整叶片叶缘时,由于电极损耗不可避免,影响工件的加工精度。通过分析成形电极及其包络运动,基于相对体积损耗比提出了一种电极损耗补偿方法,并在自研的六轴数控电火花机床上进行电极损耗补偿加工实验。结果表明:在相对体积损耗率为0.54时,补偿加工后的叶缘整体尺寸误差范围为-24.1~47.6μm,该补偿方法能有效提高叶缘加工效率和精度,实现叶缘曲面一次性电火花修整成形的目标。

It is possible to generate complex surfaces on workpiece by electrical discharge machining(EDM)using an electrode with complex surface and its complex trajectories.When the blade edge is trimmed using this method,the machining accuracy is affected due to the electrode wear during EDM.In this paper,an electrode compensation method is proposed based on the relative volume wear ratio and the enveloping motion of the electrode.The experiments were carried out on the self developed six-axis NC EDM machine.The results show that the machining error of trimmed blade edge is between-24.1~47.6μm after compensating the electrode wear under the relative volume wear rate of 0.54.It indicates that the proposed method is effective to compensate the electrode wear to improve the trimming accuracy of the blade edge and machining efficiency.