PRODUCTION OF HIGH DENSITY AND HIGH STRENGTH GRAPHITE MATERIAL

摘要

PURPOSE:To obtain a graphite material superior in density, strength and hardness by conducting a heat treatment by adding a specific quantity of an aromatic carbonization assistant compatible to a heavy oil, pulverizing, forming and calcining to make a graphite. CONSTITUTION:1-50 pts.wt. carbonization assistant consisting of an aromatic compound compatible to the heavy oil (e.g. dinitronaphthalene, dinitrobenzene) are added to 100 pts.wt. heavy oil of coal tar pitch, petroleum type pitch, etc. Next, after mixing by agitation, it is heat-treated with a delayed cocker, etc., and further calcined with a rotary kiln, etc. Subsequently a bonding agent (e.g. a phenol resin) is added to the obtained calcined coke and is blended, pulverized, formed and baked to make the objective graphite. The obtained graphite is suitably used for a crucible for single crystal silicon pulling-up device and an electrode for electric discharge machining.