SURFACE-COATED SIC WHISKERS, PROCESSES FOR PREPARING THE SAME, CERAMIC REINFORCED WITH THE SAME, AND PROCESS FOR PREPARING SAID REINFORCED CERAMIC

摘要

Disclosed are surface-coated SiC whiskers, proceses for preparing the same, a ceramic reinforced with the same, and a process for preparing said reinforced ceramic. The surface-coated SiC whiskers are SiC whiskers (I) having a surface coated with a thin carbonaceous layer having a thickness of 7 to 100 ANGSTROM , or SiC whiskers (II) having a surface coated with an Si3N4 layer. The SiC whiskers (I) can be prepared by dispersing SiC whiskers in a homogeneous solution of a thermosetting resin in an organic solvent, separating the whiskers by filtration and drying it, curing the thermosetting resin, and firing the cured thermosetting resin in a non-oxidizing atmoshpere at 800 DEG to 1,600 DEG C. The SiC whiskers (II) can be prepared by dispersing SiC whiskers in a solution of an organosilicon polymer in an organic solvent, separating the whiskers by filtration and drying it, heating the whiskers coated with the organosilicon polymer in a nitriding atmoshpere at 1,200 DEG to 1,600 DEG C. A ceramic reinforced with the SiC whiskers (I) or (II) is obtained by mixing a ceramic powder with the SiC whiskers (I) or (II) and sintering the mixed powder in an inert atmosphere or in vacuo.