| 摘要 |
<p>PURPOSE:To improve refractoriness by using silica stone as a part or the whole of silicate raw materials and adding dihydrate gypsum in a specified weight ratio based on the whole forming raw materials. CONSTITUTION:A silicate raw material partly or wholly composed of silica stone, a lime raw material such as slaked lime, a reinforcing fiber such as pulp, a filler such as wollastonite and dihydrate gypsum in an amount of 10 to 50wt.% based on the whole raw materials are blended with a large amount of water. The resultant slurry mixture is subjected to dehydration forming according to the paper making method, etc., and the formed material is then heat-treated in an autoclave at 165 to 200 deg.C. Thereby, tobermorite is synthesized from the silicate raw material and the lime raw material and dihydrate gypsum is converted to anhydrous gypsum II at the same time. After completion of treatment, the formed material is subjected to hot-air drying, thus producing the objective refractory formed material composed of calcium silicate matter, containing anhydrous gypsum II in a tobermorite matrix and having >=1.5X10<-5> ml.cm/sec.cm<2>.cm H2O permeability and >=80kgf/cm<2> flextural strength.</p> |
