Electrical Discharge Truing for Electroplated Diamond Tool : The Effect of EDM Condition and Electrode Material

Abstract

This paper describes a new electrical discharge truing (ED-truing) method for an electroplated diamond tool. This new ED-truing method can straighten a conventional electroplated diamond tool by EDMing the tips of diamond grains, which have no electrical conductivity. The appropriate EDM conditions and the electrode material for ED-truing of the electroplated diamond tool are discussed. A grinding test using the ED-trued diamond tool is also examined. It is found that a short discharge pulse is effective in EDMing diamond grains. Moreover, it is found that a Cu-W alloy electrode, which can form a conductive carbon layer uniformly on the diamond surface, is suitable for the ED-truing. It is also confirmed that there is almost a 70% reduction in surface roughness as a result of ED-truing the electroplated diamond tool.