| 摘要 |
A mechanical seal member formed by applying slurry, in which boron carbide powder and silicon powder are mixed and dispersed, onto the entire surface of a carbon material having an average pore radius of at least 1.0 mu m and formed into a hollow tubular or cylindrical product shape and firing the resultant product to form a carbon-silicon carbide composite material extending from the entire surface toward the interior of the product shape and a thin coating, 3 to 30 mu m thick, consisting mainly of silicon carbide and boron carbide and spread on the surface of the composite material. The carbon-silicon carbide composite material is formed uniformly from the surface to the center, because the member is small in size with a section, parallel to the center axis, of up to 7 x 7 mm. A silicification ratio on the surface of the composite material is 30 to 55 % in area ratio. A carbon base material density is at least 1.7 g/cm<3> and after silicification 2.0 to 2.5 g/cm<3>. A mechanical seal member may be produced by impregnating metal or resin into pores of this carbon-silicon carbide composite material. |
