Surface Roughness Research of Piezoelectric Self-adaptive Micro-EDM

Based on inverse piezoelectric effect, a new micro-EDM method called piezoelectric self-adaptive micro-EDM was proposed in this paper. The tool structure and working principle of this new method is simple and it is different from the conventional micro-EDM system. A piezoelectric actuator with high resolution and high response frequency was employed as the micro driven mechanism in this system. Because of the special structure, this new technology could regulate the discharge gap depending on discharge condition and even could realize self-elimination of short circuits during machining process. Working principle and processing of the new method was introduced, and the distinct machining characteristics were analyzed in this paper. Based on orthogonal experimental design and S/N analysis method, the effects of machining parameters such as open voltage, capacitance, current-limiting resistance, spindle rotational speed and initial feed speed on surface roughness (SR) were researched. The experimental results show that the open voltage and capacitance were the main influence factors. With the increase of open voltage and capacitance, the SR rapidly increased.