Abstract:Short arc machining is a new type of electric discharge machining, it further improves the efficiency of the discharge machining. The material removal mechanism,deionized principle and thermal phenomena in short arc machining process were discussed and the influence of the waste heat on MRR was analyzed. Under different material combination of tools electrode and workpiece electrode, the effect of peak current, pulse duration, pulse interval, feed speed, pressure and other processing factors on MRR was analyzed, which was the main index of short arc milling efficiency. Experiments show that the MRR of different electrode materials combination is different.In most discharge conditions, graphite electrode and 45 carbon steel have higher MRR, and copper the electrode and the nickel based superalloy GH4169 workpiece obtain lower MRR.