Si₃N₄ セラミックスの複合研削に関する基礎的研究

抄録

In this investigation, electro-chemical discharge grinding of Si₃N₄ ceramics is studied. This experiment consists of two main parts. One of them is electrochemical discharge experiment on Si₃N₄ ceramics and the other is combined test of electro-chemical discharge and mechanical grinding with a model wheel. The results obtained are as follows : (1) Removal amount of Si₃N₄ by electro-chemical discharge depends on kinds of electrolyte and its concentration. (2) To get the electro-chemical discharge phenomena in the electrolyte, it is necessary to give some certain voltage between electrode and electrolyte. Above this threshold voltage, removal amount of ceramics increases with applied voltage and discharge time. (3) Ceramics removal ratio (ratio of actual machined depth to setting depth of a wheel) increases by combining electro-chemical discharge phenomena with mechanical grinding. The combining way of electro-chemical discharge phenomena with mechanical grinding influences on the removal ratio. In this experiment, it is effective to give electro-chemical discharge during mechanical grinding. (4) In this combined grinding, the removal ratio decreases with increasing table speed and also it increases with increasing applied voltage. It is not influenced by wheel depth of cut. These results are explained by electro-chemical discharge frequency. (5) Form error of machined surface decreases by combined electro-chemical discharge phenomena with mechanical grinding.