| 摘要 |
PURPOSE: To force an infiltrate into a micropore by forming a dense high-heat- conductivity film of SiC on the face on the shell side of a furnace when a reduced and fired carbonaceous refractory is used. CONSTITUTION: Pitch, resin or their mixture as a binder is kneaded with a carbonaceous material selected from the conventional materials such as soil graphite and crystalline graphite or the material mixed with silicon carbide, alumina, etc., and the kneaded material is formed, reduced and fired to obtain a carbonaceous refractory block (material block) having 17-22% apparent porosity. When the block is used in a blast furnace, an SiC dense high-heat- conductivity film is formed on the face on the shell side as follows. Namely, SiCl4 heated to 300 deg.C and vaporized and the gas of a carbon compd. such as methane and carbon tetrachloride heated above the vaporization temp. are introduced into an electric furnace at 1300-1500 deg.C contg. the block with pure hydrogen as a carrier gas and allowed to react to form aβ-SiC film having 1-100μm thickness and <=10% apparent porosity on the block surface.
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