High-efficiency chilling molding sand and preparation method thereof

Abstract

The invention provides high-efficiency chilling molding sand. The high-efficiency chilling molding sand is characterized by being prepared from the following raw materials in parts by weight: 240-260 parts of chromite sand, 100-120 parts of alumina, 20-30 parts of brown aluminum oxide, 1-2 parts of nanometer carbon powder, 1-2 parts of calcium aluminate cement, 3-4 parts of alpha-Al2O3 micro powder, 10-12 parts of steel fiber, 2-3 parts of sodium tripolyphosphate, 1-2 parts of dimethyl silicone oil, 1-2 parts of ferrocene, 4-5 parts of furan resin, 2-3 parts of benzenesulfonic acid and a proper amount of water. The preparation method of the high-efficiency chilling molding sand comprises the following steps: calcining chromite sand and alumina, adding the sodium tripolyphosphate, the furan resin and the like, grinding, and finally calcining at a high temperature. The obtained high-efficiency chilling molding sand has excellent caking property, plasticity, thermal stability, air permeability and dispersity; the dispersity of the high-efficiency chilling molding sand is improved by using the alpha-Al2O3 micro powder, so that the molding sand is uniform; and the heat-conducting property of the high-efficiency chilling molding sand is improved by using the nanometer carbon powder, so that the effect of chilling castings is improved. The high-efficiency chilling molding sand is easy to mold and easy for core manufacturing. By adopting the high-efficiency chilling molding sand, the shrinkage cavity phenomenon of the castings is solved, the shrinkage porosity effect is above 90%, and the rate of finished products of the castings is improved.

Description

technical field [0001] The invention relates to the field of casting, in particular to a high-efficiency chilled 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 raw sand...

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.