The Application of Intermediate Part to Improve the Accuracy of Electrochemical Discharge Drilling

Today, the application of materials such as glass has been widely developed in the manufacture of micronutrients, electronics and medical equipment because of its high hardness, chemical resistance and high abrasion. But due to high hardness and low toughness, mechanical machining cannot be applied. The Electrochemical discharge method is a new machining method that is capable of machining hard and non-conductive electrical materials such as glass. In the process of electrochemical discharge drilling, the dimensional accuracy of the hole and especially its inlet area is important. But almost, the inlet of the hole has a high slope, which leads to excessive hole overcut and tapering of the hole side wall. In this study, to remove the high slope entrance area, a thin intermediate part was used which will be separated from the main workpiece after the drilling process. The results showed that mentioned method reduced the entrance overcut of the hole by 50 to 76% depending on the diameter of the tool. Also, the hardness measuring of points on the hole inlet showed that using the intermediate part led to the smaller heat-affected zone (HAZ) around the hole entrance.