Molding sand capable of quick air permeation and heat dissipation and preparation method thereof

Abstract

The invention relates to a molding sand capable of quick air permeation and heat dissipation, which is prepared from the following raw materials in parts by weight: 100-120 parts of return sand, 140-150 parts of quartz sand, 30-40 parts of dry coal ash, 50-60 parts of vitrified microbead, 14-20 parts of hydroxyl-aluminum pillared bentonite, 1-2 parts of sodium carboxymethyl cellulose, 20-25 parts of starch, 2-3 parts of raw tung oil, 1-2 parts of lime powder, 4-5 parts of calcium fluoride, 4-5 parts of aluminum nitride, 40-45 parts of haydite, 4-5 parts of cement and a right amount of water. The return sand, quartz sand and the like are calcined, pulverized and subjected to high-temperature calcination, and the sodium carboxymethyl cellulose and other assistants are dispersed and ground, so that the molding sand has excellent smoothness, binding property, toughness and plasticity; the vitrified microbeads are utilized to greatly enhance the air permeability and reduce the subsurface porosity; the starch is utilized to enhance the collapsibility; and the aluminum nitride is utilized to increase the heat conductivity and enhance the production efficiency.

Description

technical field [0001] The invention relates to the field of casting, in particular to a fast-breathing and heat-dissipating 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...

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.