Research On The Method And Processing Of Ultrasonic Spray EDM

Products are getting smaller and more precise in modern industrial production,and modern processing methods are promoted to developed to the direction of fine and high-precision. A new EDM method uses an ultrasonic atomizer to provide gas-liquid mixture instead of MQL was proposed in this paper. The mist created by the ultrasonic atomizer can help flushing out the debris in discharge gap. Ultrasonic cavitation is helpful in increasing MRR and improving machining stability.This dissertation summarized the international research status and development trend of EDM. The application of ultrasonic in EDM machining was analyzed. A new ultrasonic atomizer was designed on the basis of theoretical analysis, including ultrasonic power supply, transducer and dielectric supply system. Ultrasonic power uses DSP2812 as control core, mainly includes BUCK chopper module, full bridge inverter, matching circuit, EDM discharge condition detection, ultrasonic working voltage and current detection module, etc. The transducer is Langevin transducer which was designed by finite element method.Two sets of EDM drilling experiment were conducted. The first set was to evaluate the differences of wet EDM, dry EDM and ultrasonic spray EDM. The second set investigates the effects of different parameters including water flow rates, ultrasonic voltage and ultrasonic frequency. MRR and EWR were investigated in both sets of experiments. The results showed that ultrasonic spray EDM has higher material removal rate(MRR) and higher electrode wear ratio than dry EDM. Compared to wet EDM, ultrasonic spray EDM have better surface quality and lower electrode wear ratio. In ultrasonic spray experiment,the higher flow rate leads to higher MRR,within a certain range, the material removal rate increase as the flow rate increases, when outside this range, the material removal rate rise slowly, and the electrode wear rate increased significantly. The effect of voltage and frequency are multiple, general rule is that a low frequency and high voltage lead to high MRR, and the high frequency and low voltage helps reduce electrode wear rate. EDM drilling experiment was also investigated in this paper. The machining rules summarized are helpful for practical processing.