複合研削加工の基礎的研究(第1報)

Abstract

Recently, the de velopment of new materials belonging to hard machinable one has been increasing. In this situation a combined method of mechanical, electro-discharge and electro-chemical machining becomes attractive. It is called combined machining here. This type of grinding wheel which was made by electroless plating of Nickel (Ni) on a conventional WA wheel was investigated. The plated wheel has the same capability as a conventional grinding wheel and it is possible to change the ratio of usual mechanical removal action to electro-chemical romoval action with this wheel. In this paper, an experimental analysis to get the condition of making a combined machining wheel is presented. The main factors which influence onelectroless Ni plating were classified into 7 levels and studied by means of experimental analysis based on factorial design through 64 kinds of different plating conditions. The influence of the factors and their mutual effects were obtained and represented as a regressive equation. The influence of the amount of plating, composition of plating bath and circumstances of heat treatment on hardness (Hv) of plated film was investigated. As the results it is known that film hardness reaches up to 1100 Hv after heat treatment at 400°C in air or in vacuum with the bath composite NaH2PO3 20g/ l and NiSO4 40g/l. Through grinding test, it was clarified that the amount of plating and machining conditions changed the machining characteristics such as grinding force, electric current, electric current efficiency and removal rate.