| 摘要 |
PURPOSE:To improve heat resistance of a SiC sheet by adding a dispersant, org. binder and plasticizer into polycarbosilane to produce an slurry, molding a sheet from this slurry, drying to obtain a green sheet and then baking this sheet in an inert gas atmosphere. CONSTITUTION:300-500 pts.wt. of a dispersant such as a mixture solution of xylene and ethanol, 30-50 pts.wt. of an org. binder such as polyvinyl butylal, 30-50 pts.wt. of plasticizer such as dibutyl phthalate are added into 100 pts.wt. of polycarbosilane which does melt because of its three-dimensional crosslinking structure. The mixture is finely pulverized in a ball mill to obtain a slurry, and processed by removing bubbles and controlling the viscosity to obtain a highdensity slurry. Then this slurry is molded into a sheet by a doctor blade method, etc., and dried at room temp. to 100 deg.C to obtain a green sheet. The sheet is then cut into a desired size, fixed to a graphite setter and baked at 1200-1400 deg.C for about 1-2 hours in an inert gas atmosphere such as N2 to obtain a SiC sheet having the density of 1.9-2.2g/cm<2>,C/S atomic ratio of 1.55-2.00, three-point bending strength of 22-32Kg f/mm<2>. |
