Fabrication of isotropic bulk graphite using artificial graphite scrap

Abstract

Isotropic synthetic graphite scrap and phenolic resin were mixed, and the mixed powder was formed at 300 MPa to produce a green body. New bulk graphite was produced by carbon-izing the green body at 700°C, and the bulk graphite thus produced was impregnated with resin and re-carbonized at 700°C. The bulk density of the bulk graphite was 1.29 g/cm 3 , and the porosity of the open pores was 29.8%. After one impregnation, the density increased to 1.44 g/cm 3 while the porosity decreased to 25.2%. Differences in the pore distribution before and after impregnation were easily confirmed by observing the microstructure. In addition, by using an X-ray diffractometer, the degrees-of-alignment (Da) were obtained for one side perpendicular to the direction of compression molding of the bulk graphite (the "top-face"), and one side parallel to the direction of compression molding (the "side-face"). The anisot-ropy ratio calculated from the Da-values obtained was 1.13, which indicates comparatively good isotropy.