SURFACE-COATED SIC WHISKERS

• Main Authors: MINORU FUKAZAWA, KANJI SUGIHARA, TOHRU KIDA, MOTOHIRO YAMAMOTO
• Format: Patent
• Language: English
• Published: 18.09.1991
• Subjects: AFTER-TREATMENT OF SINGLE CRYSTALS OR A HOMOGENEOUSPOLYCRYSTALLINE MATERIAL WITH DEFINED STRUCTURE; APPARATUS THEREFOR; ARTIFICIAL STONE; CEMENTS; CERAMICS; CHEMISTRY; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDINGMATERIALS; CONCRETE; CRYSTAL GROWTH; LIME, MAGNESIA; METALLURGY; PRODUCTION OF A HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITHDEFINED STRUCTURE; REFINING BY ZONE-MELTING OF MATERIAL; REFRACTORIES; SINGLE CRYSTALS OR HOMOGENEOUS POLYCRYSTALLINE MATERIAL WITHDEFINED STRUCTURE; SINGLE-CRYSTAL-GROWTH; SLAG; TREATMENT OF NATURAL STONE; UNIDIRECTIONAL SOLIDIFICATION OF EUTECTIC MATERIAL ORUNIDIRECTIONAL DEMIXING OF EUTECTOID MATERIAL

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.