Mechanical Properties of Atomized Cast-iron-Diamond Composite Porous Sintered Bodies made by Pulse Electric Current Sintering Method.

Abstract

Recently, the porous cast-iron bonded (PCIB) diamond grinding wheel has been developed. Hence, it was thought that the grinding performance of the PCIB diamond grinding wheel depends on the porosity, which is the major property of a porous material. However, the influence of the porosity on the mechanical properties of the PCIB diamond grinding wheel has not been studied.In this paper, the atomized cast-iron-diamond composite sintered bodies, which had several grain volume percentages and porosities, were made by the pulse electric current sintering method. The Young's moduli and the bending strengths of these sintered bodies were measured. The relationships between those mechanical properties and the structures of the sintered bodies were examined. The results were as follows:(1) Both the Young's modulus and the bending strength of the composite sintered body increased as the porosity decreased.(2) The diamond grain size did not affect the Young's modulus, and influenced the bending strength under the experimental conditions of this study.(3) The Young's modulus depended on the diamond grain volume percentage. In the case where the atomized castiron sintered body (hereinafter referred to as the matrix) in the composite sintered body had the same porosity, the Young's modulus increased with increasing diamond grain volume percentage.(4) The bending strength of the composite sintered body with the same porosity as in the matrix depended on the bending strength of the matrix.