PROCESS FOR PRODUCING AN IMPROVED GRAPHITE BODY HAVING A LOW COEFFICIENT OF THERMAL EXPANSION

摘要

PROCESS FOR PRODUCING AN IMPROVED GRAPHITE BODY HAVING A LOW COEFFICIENT OF THERMAL EXPANSION A process for producing an improved graphite body having a very low longitudinal coefficient of thermal expansion which comprises continuously processing a carbonaceous pitch having a mesophase content of at least 40 per cent by weight into a shaped, oriented body by extrusion, spinning, or calendering; heating the shaped body produced in this manner in an oxidizing atmosphere to thermoset the body to an extent which will allow the body to maintain its shape upon heating to more elevated temperatures; further heating the thermoset body in an oxygen-free atmosphere to a carbonizing temperature to produce a highly oriented coke; admixing the coke produced in this manner with a thermoplastic carbonizable binder; and then extruding the resulting mixture into a desired shape which is in turn carbonized and graphitized. The resulting body has a longitudinal (with grain) coefficient of thermal expansion which is lower than that of like shapes prepared in the same manner from an identical binder and coke produced from the same precursor pitch by conventional delayed coking techniques.