Abstract The present experimental investigation aims at improvement of the response characteristics during electric discharge drilling process. It is a well-established fact that aspect ratio of a drilled hole in Electric Discharge Drilling (EDD) process is limited due to the occurrence of arcing and short circuiting, resulting from ineffectiveness of flushing at larger depth. The prevention of accumulation of debris during EDD is important in order to improve the material removal rate (MRR) and aspect ratio of the hole. This can be achieved by designing shaped tool electrodes which can easily evacuate the debris from the machining zone. In the present experimental investigation, a novel tool electrode has been fabricated by drilling an inclined through hole into the tool electrode (Patent pending). The proposed electrode was found effective in eliminating the accumulation of debris in the machining zone. Moreover, the need of flushing during the process has been totally eliminated making it a self-flushing electrode. The images captured using high speed camera supports the mechanism explained for the debris evacuation. The proposed electrode (diameter 0.8 mm) can drill a hole of depth greater than 9.8 mm in Ti6Al4V which is the highest depth ever reported in the literature for Ti6Al4V using electric discharge drilling. The effect on other response parameters such as machining time, hole taper and corner radius has also been investigated and compared with the holes drilled by solid cylindrical electrode. The fabrication time of the proposed electrode is lower than time reported in the literature. Therefore, the proposed electrode is capable of producing holes of high aspect ratio with minimum electrode fabrication time, thus, improving the overall productivity and reducing the cycle time.

中文翻译：

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改进电极设计以提高放电钻孔工艺性能

摘要 目前的实验研究旨在改善放电钻孔过程中的响应特性。众所周知，放电钻孔 (EDD) 工艺中钻孔的纵横比会因电弧和短路的发生而受到限制，这是由于无法在较大深度进行冲洗而导致的。为了提高孔的材料去除率 (MRR) 和纵横比，在 EDD 期间防止碎屑堆积很重要。这可以通过设计成型工具电极来实现，该工具电极可以轻松地从加工区排出碎屑。在目前的实验研究中，通过在工具电极上钻一个倾斜的通孔来制造一种新型工具电极（专利申请中）。发现建议的电极可有效消除加工区中的碎屑堆积。此外，在此过程中完全不需要冲洗，使其成为自冲洗电极。使用高速摄像机拍摄的图像支持为碎片疏散解释的机制。所提出的电极（直径 0.8 毫米）可以在 Ti6Al4V 上钻一个深度大于 9.8 毫米的孔，这是文献中使用放电钻孔对 Ti6Al4V 报道的最高深度。还研究了对加工时间、孔锥度和圆角半径等其他响应参数的影响，并与实心圆柱电极钻孔进行了比较。所提出的电极的制造时间低于文献中报道的时间。所以，