Method of making refractory bodies

Claim 1

A PROCESS FOR MAKING ARTICLES OF DENSE SILICON CARBIDE, CONTAINING LESS THAN ABOUT 5% FREE SILICON, COMPRISING: FORMING A SUBSTANTIALLY HOMOGENOUS MIXTURE OF GRANULES OF SILICON CARBIDE, A CARBONACEOUS MATERIAL COMPRISING AT LEAST ABOUT 3% BY WEIGHT OF SAID MIXTURE, AND A CARBONIZABLE MATERIAL INCLUDING A TEMPERARY BINDER, THE TOTAL AMOUNT OF CARBON IN SAID CARBONACEOUS MATERIAL AND IN SAID CARBONIZABLE MATERIAL IN SAID MIXTURE BEING BETWEEN ABOUT 85% AND ABOUT 95% OF THE STOICHIOMETRIC AMOUNT THAT IS REQUIRED TO REACT WITH SILICON TO FROM A COMPLETELY SOLID BODY OF SILICON CARBIDE FROM A SHAPE THAT IS FORMED FROM SAID MIXTURE, FORMING SAID MIXTURE TO SHAPE, SETTING SAID BINDER TO RIGIDIFY SAID SHAPE, AND FIRING SAID SHAPE AT A TEMEPRATURE OF AT LEAST ABOUT 1850* C. TO EFFECT COARBONIZATION AND BELOW THE DECOMPOSITION TEMPERATURE OF SILICON CARBIDE, IN AN ATMOSPHERE THAT WILL LEAVE ELEMENTAL SILICON AND THAT WILL NOT CAUSE THE DECOMPOSITION OF SILICON CARBIDE AND IN CONTACT WITH AT LEAST SUFFICIENT SILICON TO REACT WITH ALL OF THE AVAILABLE CARBON, THE AVERAGE BULK DENSITY OF THE CARBON IN SAID SHAPE AFTER CARBONIZATION BEING BELOW ABOUT 0.92 TO 0.93 G./CC.