1978 年 12 巻 23 号 p. 24-33
Electric discharge phenomena in electrolyte and the electro-chemical metal removal in electrochemical discharge machining (ECDM) are studied experimentally to make clear the working mechanism of ECDM. The results obtained are as follows:
(1) Discharge in electrolyte has some appearances by various electrode voltages and the unstable arc discharge is utilized for ECDM.
(2) When the electrode gap is rather wide (about 0.2mm and more) discharge takes place between the electrode and the electrolyte, but in the usual ECDM of small working gap (less than 0.1mm) discharge seems to occur between the two electrodes.
(3) In the single discharge by a rectangular wave pulse current generator an ignition delay of long duration is found out which suggests that the discharge occurs after the electrode surface has been covered by the gas evoluted in the electrochemical process.
(4) Chemical analysis of iron ion in the drainage of ECDM shows that electrochemical removal in ECDM is nearely equal to the maximum rate of electrochemical removal even if the total removal rate changes.