| 摘要 |
PURPOSE:To obtain a refractory having good heat resistance, oxidation resistance, ambient-temperature strength and high-temperature strength and improved in heat resistance by adding Ti, Y, Ce, Mg, Al or Ca to SiC and Si used as main ingredients, forming mixture thereof and calcining the mixture in N2 atmosphere. CONSTITUTION:A raw material containing 60-90wt.% SiC and 5-20wt.% Si as main ingredients and further containing one or more kinds of elements among Ti, Y, Ce, Mg, Al and Ca in the form of element or oxide in the ratio of 0.1-5.0wt.% is used. The above-mentioned raw material is mixed and formed and then calcined in >=90vol.% N2 gas atmosphere at 1200-1450 deg.C to provide the objective refractory. SiC content to be the main ingredient in the raw material composition is kept to 60-90wt.% and Si is added to the raw material in order to form Si3N4 by reaction of Si with N2 gas and provide a refractory having high toughness. For the above-mentioned purpose, >=5wt.% Si content is required and Si content is kept to <=20wt.% in order to avoid the remaining of Si. |
