Aqueous Working Fluid High Speed Arc Processing Mechanism Exploratory Research

Electrical discharge machining(EDM) is capable of machining any electrically conductive material regardless of its hardness, tenacity, brittleness and Complex cavity, for example nickel base alloy or titanium alloy, which is widely used in the industry of machine manufacturing, aviation, electric, precision machinery, instrumentation, cars, light industry. The EDM processing without cutting force, is easy to forming complicate cavity, which has great advantages in the field of hard to machining material compared with traditional Mechanical machining.The arc discharge power supply was designed based on full bridge inversion, whose switch can be controlled by IGBT. The power supply can be remote controlled with Bluetooth serial port communication. The power supply was able to supply any large discharge current under 1000 A, with high stability using the Bluetooth serial port communication.The gap phenomenon was researched observing the arc discharge progress using high speed video. The built and expansion of arc plasma channel, the expansion of bubble were analyzed. It was discovered that the arc plasma channel will expand to the electrode diameter within 2-3ms, the material removal rate in the condition of discharge duration longer than 8ms was much larger than the condition of discharge duration less than 8ms.The material removal efficiency of high speed arc machining was analyzed using metallographic analysis methods; the energy efficiency of high speed arc machining was researched using the method of measuring the debris during the arc discharge. It was discovered that the energy efficiency, material removal efficiency and material removal rate was 24 times, 19 times, 4.9×103 times with respect to the condition of traditional EDM, respectively. The temperature rise curve was measured using a type K thermocouple. The same temperature was also simulated by software of ansyis. The energy distribution ratio was got when the two temperature curve was coincided.The progress of high speed arc machining and traditional EDM was compared, whose essential differences were long discharge duration, large discharge current, material removed mainly by melting.