| 摘要 |
A heat-insulating slab or sleeve for use in lining mould heads &c. in the casting of molten metal, comprises (percentages by weight):-70 to 90% particulate refractory material, 3 to 15% clay (preferably fireclay or ball clay), up to 15% fibrous refractory material, and 0.5 to 2% phosphoric acid. The particulate refractory is sand, silica flour, grog, alumina, or chamotte, and the fibrous refractory is asbestos, slag wool, glass or metal. A resin binder comprising up to 10% b.w. of the total, may be included, e.g. phenol- or urea-formaldehyde, or furane resin. Conventional moulding processes are employed. |
