Abstract: Use the tubular sintered grinding head with random distribution of diamond particles inside as the electrode of spark-induced combustion. Electric spark discharge is induced by metallic matrix of the electrode and TC4, and though the oxygen inlet from the air intake inside of the electrode, spark-induced combustion is happened on the surface of TC4. Excessive oxide is removed by diamonds inside the electrode, and the surface quality can be improved. Test of TC4 drilling is processed. The analysis of mechanisms of processing and MRR and surface quality putted forward from park-induced combustion and finished by diamonds. And be contrasted with the drilling by EDM and normal red copper electrode. The results show that the machining efficiency of discharge combustion which is based on diamond sintered electrode is 14.5 times higher than the machining of conventional EDM drilling, and its surface quality is similar to mechanical treatment under the same experimental conditions.

Key words: mechanisms of processing, sintered electrode, spark-induced combustion, TC4