High-speed wire electrical discharge machining of insulating zirconia with a novel assisting electrode

In this paper, a novel assisting electrode is proposed for high-speed wire electrical discharge machining (HS-WEDM) of insulating zirconia. The characteristics of this HS-WEDM process based on the novel assisting electrode are investigated, which include the study of the effects of pulse-on time on machining speed, surface roughness, and the status of electrical discharge during machining. The experimental results indicate that the machining speed increases from 1.54 to 1.68mm²/min when pulse-on time is changed from 10 to 20μs and then decreases to 0.7mm²/min with increasing pulse-on time, whereas surface roughness decreases from 7.5 to 6.1 μm when pulse-on time is increased from 10 to 20μs and then fluctuates slightly with increasing pulse-on time. X-ray diffraction analysis of the machined surface indicates that chemical reactions occur during the machining process. Finally, workpieces made of insulating zirconia are machined with the HS-WEDM process.