Milling of Sintered Carbide via Electrochemical Reaction - Investigation of Machining Phenomena -

Herein, a new milling method via an electrochemical reaction is proposed to realize the high-speed machining of sintered carbide. In this method, cobalt (Co) on the surface of the sintered carbide is eluted via an electrochemical reaction, and the sintered carbide weakened by the elution of Co is scraped off with an insulating cutting edge. Results show that the cutting resistance is significantly reduced by the electrochemical reaction. However, under the conditions of a previous machining experiment, the amount of removal was low, and the machining test was conducted within a range that did not reflect the high-speed machining of sintered carbide. In this study, the conditions required to realize the high-speed machining of sintered carbide using the abovementioned method are examined. To increase the speed of electrolysis, the facing area between the tool and workpiece must be increased, and the current used for electrolysis must be increased as well. It is shown that the electrolytic current can be increased by performing machining with a large depth of cut. Consequently, the machining speed can be increased compared with that for the case without electrolysis, although a few problems remain.