This research investigates the effect of machining parameters on material removal rate, electrode wear ratio, and gap clearance of macro deep holes with a depth-to-diameter ratio over four. The experiments were carried out using electrical discharge machining with side flushing and multi-aperture flushing to improve the machining performance and surface integrity. The machining parameters were pulse on-time, pulse off-time, current, and electrode rotation. Response surface methodology and the desirability function were used to optimize the electrical discharge machining parameters. The results showed that pulse on-time, current, and electrode rotation were positively correlated with the material removal rate. The electrode wear ratio was inversely correlated with pulse on-time and electrode rotation but positively correlated with current. Gap clearance was positively correlated with pulse on-time but inversely correlated with pulse off-time, current, and electrode rotation. The optimal machining condition of electrical discharge machining with side flushing was 100 µs pulse on-time, 20 µs pulse off-time, 15 A current, and 70 rpm electrode rotation; and that of electrical discharge machining with multi-aperture flushing was 130 µs, 2 µs, 15 A, and 70 rpm. The novelty of this research lies in the use of multi-aperture flushing to improve the machining performance, enable a more uniform GC profile, and minimize the incidence of recast layer.

中文翻译：

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侧面冲洗和多孔径内部冲洗对放电加工宏观深孔特性的影响

这项研究调查了加工参数对深度与直径之比超过4的宏观深孔的材料去除率，电极磨损率和间隙间隙的影响。实验是通过采用侧面冲洗和多孔冲洗的放电加工进行的，以提高加工性能和表面完整性。加工参数为脉冲接通时间，脉冲断开时间，电流和电极旋转。使用响应面方法和期望函数来优化放电加工参数。结果表明，脉冲导通时间，电流和电极旋转与材料去除率呈正相关。电极磨损率与脉冲导通时间和电极旋转成反比，但与电流成正比。间隙清除与脉冲开启时间呈正相关，但与脉冲关闭时间，电流和电极旋转呈负相关。侧面冲洗放电加工的最佳加工条件是：脉冲接通时间为100 µs，脉冲断开时间为20 µs，电流为15 A，电极旋转速度为70 rpm。多孔冲洗的放电加工速度为130 µs，2 µs，15 A和70 rpm。这项研究的新颖之处在于使用多孔径冲洗来提高加工性能，实现更均匀的GC轮廓并最小化重铸层的发生率。脉冲关闭时间为20 µs，电流为15 A，电极旋转为70 rpm；多孔冲洗的放电加工速度为130 µs，2 µs，15 A和70 rpm。这项研究的新颖之处在于使用多孔径冲洗来提高加工性能，实现更均匀的GC轮廓并最小化重铸层的发生率。脉冲关闭时间为20 µs，电流为15 A，电极旋转为70 rpm；多孔冲洗的放电加工速度为130 µs，2 µs，15 A和70 rpm。这项研究的新颖之处在于使用多孔径冲洗来提高加工性能，实现更均匀的GC轮廓并最小化重铸层的发生率。