Cast aluminum coated sand easily-collapsible additive, coated sand and production method of coated sand

Abstract

The invention relates to a cast aluminum coated sand easily-collapsible additive, coated sand and a production method of the coated sand. The easily-collapsible additive is calcium peroxide. The cast aluminum coated sand is prepared from silica sand, phenolic resin, a curing agent, a lubricating agent and the calcium peroxide. The preparation method of the coated sand comprises the steps of: adding 1-3 parts by weight of phenolic resin and 0.1-0.6 part of calcium peroxide into every 100 parts by weight of silica sand; heating up to 100-130 DEG C, and evenly mixing; adding 0.12-0.18 part by weight of curing agent-urotropin into every 1 part by weight of phenolic resin in the obtained product, and evenly mixing; and adding 0.06-0.12 part by weight of lubricating agent-calcium stearate into every 1 part by weight of phenolic resin in the obtained product, and evenly mixing.

Description

technical field [0001] The invention relates to an additive for coated sand, a coated sand and a production method thereof, in particular to a collapsible additive for cast aluminum coated sand, a collapsible cast aluminum coated sand and a production method thereof. Background technique [0002] Aluminum castings are more and more used in all walks of life of the national economy due to their low density and light weight. However, the problem of sand cleaning of coated sand in the production process of aluminum castings has always troubled people. The reason is that cast aluminum The pouring temperature of the parts is only about 600°C, while the thermal decomposition temperature of phenolic resin is usually above 700°C, and the complete collapse temperature should reach above 1000°C. Therefore, the aluminum casting process does not have a high enough temperature to decompose the phenolic resin in the coated sand. After the aluminum casting is cooled, the coated sand still ...

AI Technical Summary

Problems solved by technology

[0005] The existing collapsing agents on the market are either powder or liquid, or participate in the reaction of phenolic resin during the production of coated sand and core making process, all of which damage the low temperature strength of coated sand (strength below 300°C) to varying degrees. , and even cause the coated sand to be unusable