Effect of Size of Graphite Flakes on the Physical Properties of the Graphite Materials

Abstract

Mesophase pitch and natural graphite flake were applied as raw materials to prepare the graphite materials by a hot-pressing technique at a relatively low temperature. In this work, the effect of mean size of natural graphite flake on physical properties and microstructure of the graphite materials were investigated. X-ray analyses, field emission scanning electron microscopy and polarized light microscopy observations indicate that the graphite blocks have highly preferred structural orientation perpendicular to the hot-pressing direction. Results shows that the graphite materials have a low electrical resistivity of 2.45μΩ·m and a high thermal conductivity of 498 W/m·K ,as well as a high bending strength of 26.71 MPa when the mean size of graphite flake in raw materials was 425μm.