Porous wear-resistant ceramic is an inorganic non-metallic material with many interconnected or closed pores. It has the advantages of high temperature resistance, corrosion resistance, high mechanical strength, good chemical stability and strong regeneration ability. Due to its functions of separation, dispersion, absorption and fluid contact, it is widely used in chemical, petroleum, chain management, textile, pharmaceutical, environmental protection and other industrial sectors, and has received more and more attention.
Pore-forming methods of porous wear-resistant ceramics include adding pore-forming agent, impregnating organic foam, sol-gel, foaming process, etc. The most common method is to add porogens, which burn out or volatilize at high temperatures and leave pores in the ceramic body. Within a certain range, the porosity increases with the increase of the porogen content. This process can prepare porous ceramic samples with complex shapes and different pore structures. Combustion or volatilization of the manufacturing agent also tends to create an "arch bridge" effect between embryo particles. This "arch bridge" effect would unsupport the green body particles and cause the sample to collapse. Therefore, the porosity of the sample is generally low, typically up to 40%, and its strength is relatively low, and the strength decreases with increasing porosity. The sol-gel method is mainly used to prepare microporous ceramic materials, especially microporous ceramic films.
The sintering temperature of porous wear-resistant ceramics is relatively high, and magnesium oxide or titanium oxide powder is mainly used as a sintering aid.
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