Anti-shelling and easy-to-fill casting sand

Abstract

The invention discloses anti-shelling and easy-to-fill casting sand. The anti-shelling and easy-to-fill casting sand is prepared from the following raw materials: talc powder, fly ash, apatite powder,zeolite, forsterite fine powder, zinc dialkyl dithiophosphate, potassium silicon fluorate, a geopolymer prepolymer, organic bentonite, sodium tripolyphosphate, polyvinyl butyral, clay and an additiveaid. Through improvement on a formula of a system, the curing rate is increased, the hardening rate of the casting sand is increased, and the shelling tendency is reduced; through optimization of thecontent of each component, the overall strength of the casting sand can be improved, the gas generating amount of the casting sand is greatly reduced and a core defect is reduced; the casting sand disclosed by the invention has very strong anti-shelling ability, a good filling property, relatively high high-temperature strength, good rigid permeability and low gas generating amount, and can significantly reduce or eliminate shelling, the core defect and other defects, effectively improve the inner and outer surface qualities of a shell core and improve the production efficiency.

Description

technical field [0001] The invention relates to the technical field of foundry sand, in particular to an anti-shell and easy-fill foundry sand. Background technique [0002] Foundry sand refers to the molding sand or core sand covered with a solid resin film on the surface of the sand grains before molding. There are two kinds of coating processes: cold method and hot method: the cold method dissolves the resin with ethanol, and adds urotropine during the sand mixing process, so that the two are coated on the surface of the sand grains, and the ethanol volatilizes to obtain casting sand; the hot method Preheat the sand to a certain temperature, add resin to make it melt, stir to coat the resin on the surface of the sand, add urotropine aqueous solution and lubricant, cool, crush, and sieve to obtain casting sand. Foundry sand is widely used in steel castings and iron castings due to its advantages of high strength, low gas generation, high dimensional accuracy of produced c...

AI Technical Summary

Problems solved by technology

However, there are also deficiencies. Shell core casting sand is prone to shelling defects in the process of making shell core sand cores, and defects such as core penetration are prone to occur in the pouring process. Therefore, the performance of the existing foundry sand must be improved to make it meet production demand

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