Artificial spherical ceramic compound sand

Abstract

The invention relates to the field of ceramic sand for casting and specifically relates to an artificial spherical ceramic compound sand. The artificial spherical ceramic compound sand can be widely applied to molding materials of industries, such as ordinary sand casting, shell mold casting and precision casting. The structure of the ceramic compound sand mainly comprises inner and outer layers;core is made from powder in large grain size: one or two of nickel tailing slag, coal gangue and coal ash; outer layer is made from powder in small grain size: one or two of flint clay, bauxite and corundum; requirement for grain size of core powder is D50 is less than or equal to 25mum; requirement for grain size of bauxite powder on outer layer is D50 is less than or equal to 13mum. The acquiredceramic compound sand has high surface quality, excellent performances, high refractoriness and low breaking rate and can be used for producing non-ferrous alloy castings, iron castings and steel castings.

Description

technical field [0001] The invention relates to the field of ceramic sand for casting, in particular to an artificial spherical ceramic composite sand, which can be widely used as molding materials in industries such as ordinary sand casting, shell casting and precision casting. Background technique [0002] Since joining the WTO, the output of castings in my country has risen steadily. my country is undoubtedly the largest casting country in the world. With the improvement of casting quality, due to some characteristics of silica sand, such as: large angular coefficient, large thermal expansion rate, etc., obviously It is no longer satisfied with the needs of the foundry industry, but high-quality natural sand such as zircon sand and chromite sand has limited reserves and high prices, which limit its application. On the other hand, due to the large amount of silica sand used in traditional sand casting, the regeneration performance is poor, causing great damage to resources ...

AI Technical Summary

Problems solved by technology

But its shortcomings are also very obvious, because the raw materials are low-aluminum or even aluminum-free materials, its refractoriness is poor, and its performance is average. It is suitable for molding materials used in castings of low-melting point alloys, but not for castings above 1600 °C ( For example: the shape of high manganese steel, etc.); in order to meet the performance requirements of high melting point alloy castings for raw sand, it is necessary to design a casting sand with high refractoriness, small thermal expansion coefficient, and good particle roundness to improve the quality of castings. Promote the development of foundry industry

And the patent publication number is that the patent literature of CN107298584A discloses a kind of ceramic sand for casting molding material, and its composition is as follows: SiO 2 Content 35~65%, Al 2 o 3 Content 30~50%, Fe 2 o 3 Content 1~10%, MnO 2 Content 1~4%, Cr 2 o 3 The content is 2-8%. The refractoriness of aluminum or aluminum-free ceramsite sand is improved, but the sintering temperature is as high as 1550°C-1700°C, and the sintering time is 3.5-5 hours. The sintering temperature is too high and the holding time is too long , not only wastes energy and increases costs, but also the sintering temperature of the existing sintering rotary kiln is mostly lower than this sintering temperature, and there is a large technical bottleneck

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