Preparation and properties of graphite/ceramic conductive composites

In order to investigate the effects of the plate graphite content and its preferred orientation on the structure and property of graphite/ceramic composites，graphite/ceramic conductive composites were prepared from the ceramic matrix (albite，diopside，quartz) and graphite by wet-mixing，drying，granulating，and rapid sintering processes. The electric resistance along directions perpendicular and parallel to the molding pressure was accurately measured. The grain phases and the fracture surface micrograph were analyzed with XRD and SEM. The results show that the ceramic matrix reacts hardly with the graphite in the sintering process and no new phase is found. The plate graphite of the graphite/ceramic conductive composites is oriented，and the c-axis of graphite inclines to be parallel to the direction of the molding pressure. The resistivity of graphite/ceramic conductive composites is anisotropic. With the increase of the graphite content，the resistivity of composites rapidly decreases. However，it decreases very slowly when the graphite content exceeds 15 wt%.