中文摘要：

在电火花小孔加工中，采用普通铜管电极加工后，孔的圆柱度差，出现锥孔、工具电极端部变钝等现象。主要原因是由于电蚀产物在加工侧隙的二次放电造成的。普通铜管电极表面喷涂Al2O3陶瓷材料，可以有效的降低二次放电的发生，提高加工质量。采用Al2O3／Cu复合电极和普通铜管电极，在D703F电火花小孔机床进行加工。在不同的脉冲宽度和脉冲电流下，使用两种电极对同一工件进行加工。实验结果表明，与普通铜管电极相比，复合电极相对损耗降低30％，孔和工具电极锥度减小，提高了孔的形状公差等级。

英文摘要：

After processing by ordinary copper tubular electrode, in small hole EDM drilling, the cflindricity of the hole was poor, and the phenomenon of tapered bore and the tubular electrode terminal portion was blunted. The main reason was the second discharge of the electrolytic corrosion product in the processing side. It can effectively reduce the occurrence of secondary discharge through sprayed Al2O3 ceramic material on the ordinary copper tubular electrode and improve the processing quality. The processing used Al2O3/Cu composite electrode and ordinary copper tubular electrode in the D703F EDM hole machine. The workpiece processing in two type electrodes with variation of pulse on time and current. The performance of the composite electrode, compared with ordinary tubular copper electrode, shows that, the electrode relative loss reduced 30%, hole and toll electrode taper is decreased, and the shape of the hole tolerance level is improved.