| 摘要 |
PURPOSE:To obtain a sintered mullite composed of WC, MgO and mullite and having excellent high-temperature strength at a low cost by using WC and MgO at respective specific ratios to mullite and adjusting the particle diameter of the mullite to a prescribed value. CONSTITUTION:The objective composition is composed of WC, MgO and mullite and has a WC content of 3-40wt.% and an MgO content of 1-10wt% based on the mullite. The particle diameter of the mullite is 10-100mum. The sintered mullite can be produced by using at least two kinds of substances selected from purified clay mineral, Bayer alumina, aluminum hydroxide and quartzite as main raw materials, compounding the materials to attain an Al2O3/SiO2 ratio falling within mullite-forming range, crushing the compounded raw material in wet state until >=90% of the mixture is crashed to <=5mum in diameter, adding 3-40wt.% (based on the compounded raw material) of WC having particle diame ter of <=50mum and 1-10wt.% of MgO having particle diameter of <=1mum, mixing the components, drying and crushing the mixture, forming by using an organic binder and burning at >=1600 deg.C for >=1hr. |
