Anti-sticky calcium carbonate molding sand and preparation method thereof

Abstract

The invention discloses anti-sticky calcium carbonate molding sand which is characterized by consisting of the following raw materials in parts by weight: 70-80 parts of bentonite, 230-240 parts of calcium carbonate, 15-20 parts of corn flour, 40-45 parts of sawdust, 24-28 parts of rice chaff, 2-3 parts of inositol hexaphosphate, 15-20 parts of barium sulfate, 2-4 parts of polyvinyl alcohol, 1-2 parts of coal tar, 30-35 parts of talcum powder and a proper amount of water. According to the anti-sticky calcium carbonate molding sand, the calcium carbonate is used as a main raw material, is subjected to calcining, dispersive grinding and high-temperature calcining and then is combined with the bentonite, so that the molding sand is high in cohesiveness, flexibility, plasticity and smoothness; furthermore, the sawdust and the rice chaff are used, so that the molding sand is high in ventilating property, collapsibility and anti-sticky property; the brightness of a casting is greatly improved, the shrinkage cavity phenomenon is alleviated, and the damage rate of the casting is reduced.

Description

technical field [0001] The invention relates to the field of casting, in particular to an anti-adhesive calcium carbonate molding sand and a preparation method thereof. Background technique [0002] Molding sand is a material used for molding in casting. Molding sand is generally made by mixing molding materials such as raw sand for casting, molding sand binder and auxiliary additives in a certain proportion. Natural silica sand containing clay can also be used. In the usual molding sand formula for aluminum casting, the particle size of the molding sand is too large or If it is too small, the diameter of the molding sand is too large. Although the air permeability is good, the surface of the aluminum sand parts is rough and the finish is not good. If the diameter of the molding sand is too small, the air permeability of the sand mold is not good, and the aluminum castings have pores. Coal powder clay green sand, which is widely used at home and abroad, is generally made of...

AI Technical Summary

Problems solved by technology

Molding sand is generally made by mixing molding materials such as raw sand for casting, molding sand binder and auxiliary additives in a certain proportion. Natural silica sand containing clay can also be used. In the usual molding sand formula for aluminum casting, the particle size of the molding sand is too large or If it is too small, the diameter of the sand material is too large. Although the air permeability is good, the surface of the aluminum sand parts is rough and the finish is not good. The diameter of the sand material is too small, resulting in poor air permeability of the sand mold and air holes in the aluminum casting

Coal powder clay green sand, which is widely used at home and abroad, is generally made of raw sand, binders, coal powder additives, etc. and water. It has a certain anti-sticking sand effect, low material cost, and high production efficiency. However, its consumption is large, the emission is serious, and the coal powder is burned and decomposed in the casting process to produce toxic gas pollution.