| 摘要 |
PURPOSE:To obtain a sintered beta-type SiC having excellent mechanical properties, containing little alpha-phase and free from abnormally grown particle by sintering high-purity beta-type SiC powder having restricted metal impurity content, BET specific surface area and 2Halpha-phase content in a non-oxidizing atmosphere at a specific temperature. CONSTITUTION:Fine silica powder having low metal impurity content is mixed with fine carbon powder having low ash content at a C/SiO2 molar ratio of about 2.8-4 and the mixture is reacted by hating at a high temperature in a non-oxidizing atmosphere to obtain high-purity beta-type SiC powder having a metal impurity content of <=0.1wt.%, a BET specific surface area of 12-20m<2>/g and a 2Halpha-phase content of 5-1wt.%. The high-purity beta-type SiC powder is added with a sintering assistant such as boron and sintered at 1,900-2,100 deg.C in a non-oxidizing atmosphere to obtain the objective sintered beta-type SiC. |
