Brief description of Sunrise refractory hot-selling zirconium mullite brick with compatative price

Zirconium mullite bricks improve the structure of mullite by introducing ZrO2 into the A1203-SiO2 bricks, which can improve the chemical corrosion resistance, thermal shock resistance and reduction of expansion coefficient of mullite. Stone bricks, commonly known as zirconium mullite bricks, are generally produced by electrofusion and are also produced by sintering.

 

Sintered zirconium mullite brick is a special refractory material made by introducing zirconia into mullite matrix by using industrial alumina and zircon concentrate as raw materials. The introduction of zirconia into mullite bricks and the use of zirconia phase transformation toughening can greatly improve the high temperature mechanical properties of mullite materials. Zirconium oxide promotes the sintering of mullite materials. The addition of ZrO2 accelerates the densification and sintering process of ZTM materials due to the formation of low melting materials and the formation of vacancies. When the mass fraction of ZrO2 is 30%, the relative theoretical density of the body fired at 1530C reaches 98%, the strength reaches 378 MPa, and the toughness reaches 43 MPa.

Zirconium mullite bricks prepared by reaction sintering using industrial alumina and zircon as raw materials are difficult to process due to simultaneous reaction and sintering. Usually, it is first densified at 1450C during firing, and then densified, and then heated to 1600C for reaction. ZrSi04 is decomposed into ZrO2 and SiO2 at more than 1535C, wherein SiO2 and A1203 react to form mullite, which is partially decomposed due to ZrSi04. The liquid phase appears, and the decomposition of ZrSiO4 can refine the particles and increase the specific surface area to promote sintering.

 

Studies have shown that when the addition amount of zircon is less than 54.7%, the microstructure of the sintered sample gradually transitions from a network of columnar corundum to a network structure composed of columnar mullite as the amount of zircon added increases. . The high-temperature flexural strength of the sample (1400 ° C also increases with the increase of zirconia content, when the zirconia content is 23.7% - the larger value, and then the strength decreases. The addition of cobalt oxide helps to resist heat Increased shock.