A kind of sponge alumina and its preparation method and application

Abstract

The invention provides sponge aluminum oxide and a preparation method and application thereof. The preparation method of the sponge aluminum oxide comprises the following steps of using an aluminum oxide aggregate soaked by an aluminum oxide sol as a calcining raw material, wrapping the surface of the aluminum oxide aggregate by an aluminum oxide sol layer containing aluminum oxide, and calcining, so as to obtain the sponge aluminum oxide with a coating structure that the inner layer is a porous aluminum oxide aggregate and the outer layer is a latticed aluminum oxide wrapper. The special sponge structure body with the coating structure can greatly improve the anti-heat vibration property and high-temperature toughness of the aluminum oxide. The sponge aluminum oxide has the advantages that the anti-heat vibration property and high-temperature toughness are excellent; the sponge aluminum oxide can be directly applied to various fire-retardant or ceramic products to improve the anti-heat vibration property and high-temperature toughness of the product, the degrading of the high-temperature property caused by the production of other low-temperature phase or glass phase is avoided, and the influence to the size accuracy of the product due to the production of the second phase in the shaped products is also avoided.

Description

technical field [0001] The invention relates to the field of alumina refractory materials, in particular to a sponge alumina and its preparation method and application. Background technique [0002] The current refractories or ceramic corundum products are generally directly added ɑ-Al 2 o 3 , various corundum or other alumina raw materials to improve the high temperature performance of the product, the thermal shock resistance of the product is not very ideal, in order to improve the thermal shock performance or improve the toughness of the product, it is often formed by adding other materials to form the second phase or Is the reaction to form tiny cracks. [0003] The method of adding other materials to form a second phase or react to form tiny cracks is difficult to mix evenly during the production process, and the weighing process is also prone to deviations. The firing process requires high temperature control, and it is easy to produce large cracks, or temperature r...

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Problems solved by technology

[0003] The method of adding other materials to form a second phase or react to form tiny cracks is difficult to mix evenly during the production process, and the weighing process is also prone to deviations. The firing process requires high temperature control, and it is easy to produce large cracks, or temperature rise and fall If the speed is too fast, it is easy to form a glass phase, and the size of the product exceeds the requirement due to two times of mullitization and spinelization, and the reaction temperature may not have been reached in the castable. to improve toughness

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