| 摘要 |
PROBLEM TO BE SOLVED: To obtain a reaction-sintered ceramic improved in strength and fracture toughness by partially generating chemical reactions in the calculation product of the powder of raw materials to advance the chemical reactions in local zone regions. SOLUTION: The mixture of an organic binder and the powder of elements composing a (non)oxide ceramic matrix is press-molded into the molded product having a density of 75-79%. The molded product is subjected to a binder- removing treatment and subsequently to a calculation treatment. The calculation product 13 is placed in a thermally treating oven in which divided heaters 9 are arranged on the inside of a heat-insulating wall 8, and elements 12 required for forming the final product, ceramic, of the calculation product are charged in the reservoir 11 of a bulkhead chamber 10. The oven is heated at 1300-1450 deg.C to supply the gaseous elements 12 in a pressure of >=0.1atm, and simultaneously a chemical reaction-occurring part is moved at a rate of 1-200mm/min to subject the calculation product to a zone reaction sintering treatment. Thus, the reaction-sintered ceramic having an orientation degree (ball figure method) (F value) of >=0.5, a relative density of >=95%, and a residual raw material composition of <=1vol.%. |
