1960 年 29 巻 6 号 p. 405-411
The electric spark machining has recently been put to practical use in precision machining and has been developed rapidly. This paper deals with one of the causes that give rise to the difference in electric erosion by reversing the polarity of the spark.
Observation is made on the ratio of anodic to cathodic erosion of various metals. By crater measurement, single discharge between metals of the same kind is found to cause erosion more on the cathode than on the anode. By successive discharges in spark machining, however, the erosion is more on the anode. This is explained as due to a layer of electrified metal chips being formed on the cathode which is confirmed experimentally.