Silicate inorganic binder for casting and method for preparing silicate inorganic binder for casting

Abstract

The invention relates to a silicate inorganic binder for casting and a method for preparing the silicate inorganic binder for casting. The silicate inorganic binder for casting consists of crystalline water-contained sodium metasilicate, boric acid, sodium tripolyhosphate and an organic modifier. The silicate inorganic binder for casting is high in binding property, long in storage time, nontoxic and harmless and low in cost; the inorganic binder prepared by the method is high in wettability and binding property; and the molding sand made by the silicate inorganic binder is high in flowability, low in gas forming property, long in storage time and high in applicability, and the old sand can be recycled.

Description

technical field [0001] The invention relates to a casting sand bonding material, in particular to a silicate inorganic bonding agent for casting and a preparation method thereof. Background technique [0002] At present, casting sand binders include organic and inorganic. Since organic binders are mostly resins, because they are organic polymers, in the casting production process, from sand mixing, core making, pouring, cleaning The disposal of waste sand will have adverse effects on the human body and the environment. In addition, most resins are petroleum derivatives, which are non-renewable resources and costly. The inorganic binders are mostly sulfates, phosphates, water glass, and modified water glass modified on the basis of medium and high modulus water glass. However, the molding sand cast with sulfate-based inorganic binders has problems such as low strength and high casting defect rate; the mold sand casted with phosphate-based inorganic binders has problems such...

AI Technical Summary

Problems solved by technology

However, the molding sand cast with sulfate-based inorganic binders has problems such as low strength and high casting defect rate; the mold sand casted with phosphate-based inorganic binders has problems such as poor moisture resistance and short service life, while water glass and modified The molding sand of water glass casting is superior to the former two in terms of strength, precision, production efficiency and environmental protection, so water glass and modified water glass are mostly used as molding sand binders in casting

However, due to the poor aging resistance of water glass and modified water glass, the bond strength is reduced, and the molded sand has poor storage resistance, poor applicability, poor moisture resistance, poor collapsibility, and poor core making. Problems such as low efficiency and difficulty in regeneration and reuse of old sand