Effect of Discharge Condition on Cavitations Behavior by Single Pulse Discharge

Abstract:

This paper describes some experimental results on a fundamental phenomenon of the single pulse discharge. In electrical discharge machining (EDM), processing accuracy was effected by behaviors of fused material. Pressure was important for removing fused material. So, it was needed to clarify that the mechanism of pressure occurrence by electrical discharge. In this study, it was investigated that effect of discharge condition on cavitations behavior by single pulse discharge. Gap region medium viscosity was changed by medium and temperature. Electrical discharge current was changed by applied voltage. The optical fiber vibration sensor is located on an aluminum work-piece (cathode) plate. Pressure was measured by optical fiber sensor during single pulse discharge. As the results, burst acoustic emission (AE) wave was occurred during single pulse discharge. The occurrence of several times burst AE wave was caused by cavitations behavior. The condition on which bubble does not collapse has become apparent. It was found that cavitations behavior was mainly depended on discharge current except for the condition on which bubble does not collapse.

• Periodical: Key Engineering Materials (Volumes 523-524)
• Pages: 951-956
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.523-524.951
• Online since: November 2012
• Authors: Yoshiaki Akematsu, Kazuro Kageyama, Naotake Mohri, Hideaki Murayama
• Keywords: Cavitation, Electrical Discharge Machining (EDM), Optical Fiber Sensor (OFS)

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