Foundry mold treating compositions and methods of making same
AssigneeGeneral Electric Company
InventorsWayne F. Wales, James J. Frawley
Life of this patent
Estimating the term…
Abstract
Phosphosilicate compositions are disclosed for treating foundry molds and like products to enhance mold strength and refractoriness. The phosphosilicates, characterized more specifically as silicyl metaphosphates, may be used in combination with select refractory aggregates and other additives to form mold surface treating compositions, or may be combined directly with foundry sand or other comminuted refractory material for compacting into a mold form.
Claims22
A phosphosilicate composition useful for treating foundry molds and products, comprising an admixture of from about 5 to about 55 weight percent colloidal silica sol containing at least 15 percent SiO.sub.2 ;
- from about 2 to about 60 weight percent of an alkyl silicate containing at least 28 percent SiO.sub.2 ;
- from about 20 to about 40 weight percent of a water-miscible organic solvent, and from about 5 to about 45 weight percent phosphoric acid having a concentration of at least 50 percent.
A composition for treating foundry molds and products, obtained by:
- (a) admixing from about 20 to about 40 weight percent of a water-miscible organic solvent;
- from about 5 to about 55 weight percent colloidal silica sol containing at least about 15 percent SiO.sub.2 ;
- and from about 2 to about 60 weight percent of an alkyl silicate containing at least about 28 percent available SiO.sub.2 ;
- and
- (b) reacting from about 5 to about 45 weight percent phosphoric acid having a concentration of about 50 to about 90 percent with the admixture obtained by step (a) to yield a phosphosilicate compound.
A method of treating foundry molds and products formed of compacted comminuted refractory materials, comprising coating at least a predetermined surface portion of the surface to be treated with a hybrid silicate followed by application to the surface so treated of a mixture of about 50-90 percent of a high concentrate phosphoric acid and approximately 10-50 percent water miscible alcohol to form a silicyl metaphosphate on the surface so treated.
Dependencies are inferred from the claim text.