Research On The Ultrasonic Hybrid EDM Machining Of Super-hard Materials

Super-hard material has characteristics of high hardness and high wearability. It is difficult to machine it by the traditional mechanical method. Non-traditional machining is an effective way to process the super-hard material. In the difficult-to-cut material machining and precision machining, the ultrasonic machining technology has the effect that general processing technology can not match. The combination of ultrasonic machining and electrical discharge machining (EDM) can greatly improve the processing speed and quality. This technique can complete the processing work that general processing method can not finish. Therefore, it has been widely used in various national departments and has broad application prospects.In this paper, the mechanism of ultrasonic hybrid EDM in super-hard material processing and the properties of super-hard alloy, polycrystalline diamond (PCD) and conductive ceramic are introduced. The effect of ultrasonic vibration on the gap discharge status, discharge channel and the surface microstructure is studied. A set of experiments are designed to machine the three kinds of super-hard material with ultrasonic hybird EDM. In this way, the impacts of pulse width, ultrasonic amplitude and abrasive size on the processing efficiency are obtained. The attrition of the electrode are also introduced here. The impact of EDM process on ultrasonic machining and the discharge situation are analyzed. The results show that EDM has some impact on the efficiency and accuracy of ultrasonic machining.The discharge of EDM in the experiment is a complex process.The results also show that the material removal rate increases if the pulse width and ultrasonic amplitude increase. Surface roughness becomes larger when the pulse width and ultrasonic amplitude increase. The size of abrasive particles also has a certain impact on the roughness.