| 摘要 |
1283692 Hot tops FOSECO INTERNATIONAL Ltd 16 Sept 1969 [25 Sept 1968] 45583/68 Heading C3N [Also in Division D2] A refractory heat-insulating material, suitable for lining risers and hot tops in the casting of metals, comprises 1-20% by weight of particles of aluminium, magnesium, silicon or zirconium, 10-97% by weight of fibres of alumino-silicate, zircon or silica and a binding agent comprising an organic binder and colloidal silica sol. It may also contain 10-87% of refractory filler particles, e.g. crushed coke, alumina, magnesia or silica. The organic binder may be an organic gum, starch, or a natural or synthetic resin. The metal in the composition serves to reduce any oxides on the surface of the metal being cast. The material is preferably formed by slurrying the ingredients in water and dewatering on a foraminous mould. In the example, slurries contain: (1) aluminosilicate fibre, aluminium powder, colloidal silica sol and starch; (2) aluminosilicate fibre, starch, colloidal silica, aluminium powder, alumina and aluminium sulphate; (3a) aluminosilicate fibre, starch, colloidal silica sol and aluminium sulphate; and (3b) as 3a plus aluminium powder. |
