ABSTRACT
Micro EDM is a kind of non-contact machining technology, which has the advantages of small macro cutting force and wide range of material application, but because of the precision of micro EDM, high discharge energy, small tool electrode size, easy to cause chip removal difficulties, resulting in unstable state of micro EDM, low machining efficiency and poor quality. In order to improve the environment and efficiency of micro EDM, this paper proposes the use of piezoelectricity based on micro EDM. A new EDM method of piezoelectric ceramic transducer (PZT) for synchronously excited compression discharge channel, which uses PZT when driving voltage of the actuator increases and compresses, the actuator will produce a small amount of elongation and retraction, which can effectively improve the state of the discharge gap, reduce the loss of the electrode, and increase the voltage of the actuator efficiency. In this paper, research on the optimization of process parameters for MRR in PZT Excited Discharge Channel Compression Micro-EDM is carried out by means of orthogonal test and signal-to-noise ratio analysis. The open circuit voltage, pulse width, pulse frequency and peak current are studied according to the large characteristic of SNR. The SNR of material removal rate(MRR) is calculated, and the optimal parameter combination to achieve single machining target is obtained. The reliability of the optimization results is verified by experiments. The experiment shows that the open circuit voltage and pulse width are raised in the orthogonal experiment aiming at improving the material removal rate of workpiece. The material removal efficiency increases with the increase of open circuit voltage and pulse width, decreases first and then increases with the increase of pulse frequency, and increases with the peak value current increases first and then decreases.
