Binder for improving the hardening strength of molding sand

Abstract

The invention discloses a binder for improving the hardening strength of molding sand, and relates to the technical field of casting. Phosphoric acid and maleic acid are mixed and then heat treatmentis carried out to obtain mixed acid; the mixed acid is added to water to prepare a mixed acid solution; and aluminum hydroxide and sodium carbonate are added to the mixed acid solution, ultrasonic treatment is performed for 3 to 5 minutes to obtain a reaction solution, and then the reaction solution is stirred at the rotating speed of 500r/min and 1500r/min respectively for 1 to 1.5 hours to obtain transparent liquid, that is the binder is obtained. The invention provides the binder for improving the hardening strength of the molding sand; the binder prepared by the invention is applied to a sand mold; under the promotion of microwaves, the hardening time can be shortened greatly, the production efficiency is improved, meanwhile, the instant strength can be greatly improved, and the binderhas more excellent collapsibility, low retained strength and is more conducive to recycling.

Description

technical field [0001] The invention belongs to the technical field of casting, in particular to a binder for improving the hardening strength of molding sand. Background technique [0002] Casting is the process of smelting metal into a liquid that meets certain requirements and pouring it into a mold, cooling and solidifying, and cleaning to obtain a casting with a predetermined shape, size and performance. Because the casting blank is almost formed, the purpose of free machining or a small amount of machining reduces the cost and reduces the production time to a certain extent. Casting is one of the basic processes of the modern device manufacturing industry. [0003] Molding sand mainly includes sand casting and special casting. Ordinary sand casting uses sand as the mold material, also known as sand casting and foundry, including wet sand mold, dry sand mold and chemically hardened sand mold. The advantage is that the cost is low, because the sand used in the mold can ...

AI Technical Summary

Problems solved by technology

Ordinary sand casting uses sand as the mold material, also known as sand casting and foundry, including wet sand mold, dry sand mold and chemically hardened sand mold. The advantage is that the cost is low, because the sand used in the mold can be reused; the disadvantage is that the mold is made Time-consuming, the mold itself cannot be reused, and the finished product must be destroyed

[0004] Casting with ordinary molding sand requires a molding sand binder to bond the original sand (mountain sand or river sand) together to avoid collapsing. However, the existing molding sand binder uses clay as a binder. Although clay is relatively viscous, its use as a binder will lead to poor collapse of the sand mold and low instant hardness, which will cause various casting defects and reduce casting costs

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