Improving the packing and mechanical properties of graphite blocks by controlling filler particle-size distribution

Abstract

Mechanical qualities play a critical role in increasing the industrial applications of carbon-carbon composite materials as their porosity determines the strength of the material. In this study, carbon blocks with improved packing properties were produced by controlling various particle size distributions of coke particles. Particle-size diversity and geometric packing structure favorably affected the packing properties of the powder. Coke samples with tap densities up to 1.258 g/mL were prepared by controlling the size distribution of the coke particles. The porosity of the carbon block was calculated using three density definitions. The closed pores were reduced by up to 13.68% through the packing density of the particles, and the open pores were controlled by the coke/pitch mixing conditions regardless of the tap density. The carbon block showed a total porosity of 21.61% and a maximum compressive strength of 131 MPa by controlling the tap density of the coke. The proposed technique will be useful in various industries that require appropriate tap density control and will improve the compressive strength of composite materials.