Refractory insulating compsn for hot tops - comprising alumino silicate fibres, inorg binder, starch and opt inorg filler

摘要

Refractory fibre based insulation compsn. comprising by wt. 30-50% refractory fibres, more than half of which are aluminosilicate, 5-45% inorganic binder, 2-10% organic binder and 5-35% of a refractory filler, incorporates 1-35% granular silicon carbide, =80 wt.% of which are 60-325 mesh particles. The inorg. binder is pref. a mixt. of colloidal silica and clay, the organic binder is pref. starch and the refractory filler is a granular aluminosilicate. Used for insulating gates and hot tops for metal casting moulds, esp. for casting molten ferrous alloys. Compsn. provides a thermally and chemically resistant article which is elastic, self supporting and conserves its shape, which is esp. resistant to corrosion by the molten metal and does not produce excessive noxious fumes by reason of combustion of organic binder as in prior art.