アトマイズ鋳鉄 ダイヤモンド複合粉末のパルス通電焼結特性

Abstract

The porous cast-iron bonded diamond grinding wheel showed the high grinding performance for the hard-to-grind ceramics. Hence, it is considered that the grinding performance of the said diamond grinding wheel depends on the porosity, which is the major properties for porous material.In this paper, to control the porosity of the porous cast-iron bonded diamond grinding wheel, we studied pulse electric current sintering behavior of atomized cast-iron-diamond composite powder. The results were as follows:(1) The cast-iron powder was deformed plastically at the contact between the diamond grain.(2) The porosity control of the atomized cast-iron-diamond composite sintered body could be performed independently of the volume fraction and the size of the diamond grain by the pulse electric current sintering method.(3) Both the volume fraction of diamond grain and the diamond grain size affected significantly the apparent density of the green body, because the extra pores were generated at the contacts between the atomized cast-iron powders and the diamond grains.(4) The densification of the atomized cast-iron powders in the composite sintered body was affected by the volume fraction of diamond grain, and was not influenced by the diamond grain size.