High-strength composite salt core material for low-melting-point alloy casting, salt core and preparation method

Abstract

The invention belongs to the technical field of casting, and particularly relates to a high-strength composite salt core material for low-melting-point alloy casting. The high-strength composite salt core material comprises, by mass, 70%-100% of water-soluble inorganic salt and 0%-30% of a reinforcement, wherein the water-soluble inorganic salt comprises one of low-melting-point salts including potassium nitrate and sodium nitrate, and at least one of high-melting-point salts including potassium chloride, sodium chloride, potassium bromide and sodium bromide, and positive ions of the low-melting-point slats are the same as positive ions of the high-melting-point salts. The invention further discloses a preparation method of a high-strength composite salt core, and an obtained salt core product. The prepared composite salt core has extremely high bending strength, excellent hygroscopicity and small volume shrinkage, and the comprehensive performance is excellent. In addition, the preparation technique of the high-strength composite salt core is simple, raw materials are cheap, and industrial production is easy.

Description

technical field [0001] The invention belongs to the field of casting technology, and more specifically relates to a high-strength composite salt core material for low-melting point alloy casting, a salt core and a preparation method. Background technique [0002] With the continuous development of the foundry industry, castings are widely used in aerospace, mechanical instruments, and daily life, and the demand is increasing day by day, so the requirements for their performance are becoming more and more stringent. These castings often have complex cavities or slender channels, and generally need to be formed by core casting. [0003] At present, casting cores usually include resin sand cores, ceramic cores, water-soluble salt cores, and the like. The strength of the resin sand core is low, the production workshop smells heavy, and it pollutes the environment; the strength of the ceramic core is high, but its preparation cost is high, and the post-casting cleaning process h...

AI Technical Summary

Problems solved by technology

The strength of the water-soluble salt core is low, the shrinkage is large, the surface of the salt core is more wrinkled, and the reinforcing whiskers used are expensive, which increases the production cost

[0005] CN104399865A discloses a method for preparing an aluminum piston gravity casting water-soluble graphite composite salt core. The method uses graphite as a reinforcing phase, and metal halide salts are water-soluble salts. The prepared salt core has higher strength and smaller shrinkage, but The water-soluble salt core prepared by this invention has a low graphite density during the preparation process, it is difficult to mix evenly, and it is easy to layer, and at the same time, the equipment requirements for salt core preparation are also very high

[0007] The above-mentioned water-soluble salt cores are mostly used in the casting of high-melting-point alloys such as aluminum alloys. When used for die-casting of low-melting-point alloys, it will inevitably lead to high energy consumption, which is not conducive to industrial applications. In addition, the above-mentioned water-soluble salt cores have expensive raw materials. Therefore, how to prepare a low-melting-point alloy (alloy with a melting point within 500°C, such as zinc alloy) die-casting low-energy, high-strength water-soluble Salt core is an urgent problem to be solved

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