Scanning process of spark assisted chemical engraving (SACE) on ZrO2 ceramics by constraining discharges to tool electrode end

摘要

Zirconium dioxide (ZrO2) is a ceramic material used in a wide range of applications. However, the mechanical properties of ZrO2 ceramics, such as brittleness, high hardness, and high temperature resilience, make it challenging to machine. SACE (spark assisted chemical engraving) is an advanced technology for machining ZrO2 ceramics that has also been used successfully in glass machining. However, the sidewall of the SACE tends to generate spark discharges, which not only waste energy but also affect machining accuracy. In a set of exploratory SACE experiments, it was found that a large percentage of discharges occur at the end of the tool electrode under certain conditions. It is believed that the sharp square edge of the tool-electrode end is conducive to the end discharges by large. Therefore, a cylindrical notched tool electrode with an increased number of sharp edges to improve discharge constraint is proposed in the SACE process. SACE scanning experiments were conducted on ZrO2 ceramics using the proposed tool electrode and found that it significantly improved machining efficiency and accuracy.