How is zirconia ceramics sintered at low temperature? With the continuous development of society, zirconia ceramics have been widely used in the field of structural ceramics. Zirconia ceramic sintering is a very important process. The quality of sintering will directly affect the subsequent ceramic processing, so only the sintering temperature is adjusted properly. Its embryo body will be perfect. Zirconia ceramics can be sintered in many ways. So how does zirconia ceramics undergo low-temperature sintering? The following is an introduction by the staff of Shenzhen Jinlongda:

1. Low temperature sintering using powder

The preparation methods of easy-sintering powders are roughly divided into general powder preparation processes and special powder preparation methods. The difference between them is mainly the difference in the preparation process. The preparation process referred to here is the chemical composition of the mother salt, the preparation conditions of the mother salt, the calcination conditions, the pulverization conditions, etc.

With the miniaturization of powder particles, the microstructure and performance of the powder will undergo great changes, especially for sub-micron to nanometer powders, it will have internal pressure, surface activity, melting point, etc. There are unexpected performance. Therefore, the powder that is easy to sinter can accelerate the dynamic process, reduce the sintering temperature and shorten the sintering time during the sintering process.

2. Low temperature sintering with the introduction of additives

Additives can make the material show new functions, improve strength, inhibit grain growth, promote sintering, etc. This method can be divided into the following two categories according to the action mechanism of additives: the introduction of additives increases the lattice vacancy, which is easy to diffuse and accelerates the sintering rate; the introduction of additives makes the liquid phase formed at a lower temperature, and the crystals appear after the liquid phase. Can make viscous flow and promote sintering.

The above description of how to perform low-temperature sintering of zirconia ceramics is here. Zirconia ceramics are widely used in industrial production. The preparation of zirconia ceramics through low-temperature sintering can reduce energy consumption and thereby reduce product costs. Generally, the surface of high-quality zirconia ceramics is white, yellow or gray when it contains impurities, but it will become yellow after sintering.

Why does zirconia ceramic turn yellow after sintering:

1. Is the sagger or layered slab you use new? If it is new, you need to burn it several times before sintering the product;

2. Is the temperature in the high temperature zone too high? Is the chimney of the furnace well ventilated;

3. Is the product stacked too much? Without burning in an oxidizing atmosphere, there are oxygen vacancies, and the product will have a color.

4. The raw material of zirconia ceramic contains impurities. Iron impurities will turn yellow in oxidation. If there is too much yttrium doping, there will be color. It is recommended to open the furnace lid, the effect may be completely different.

5. The final issue may be the internal pollution of the furnace.

Treatment method for yellowing of zirconia ceramics:

Use white vinegar and lemon peel. First wipe off the dirt on the surface of the sanitary ware, and then wipe the surface of the sanitary ware with a soft cloth dipped in a little white vinegar or wipe with lemon peel, the sanitary ware will be as bright as new.

The reason why the above zirconia ceramics turn yellow after sintering is introduced here. The sintered Y toughened zirconia ceramics are white at 1450°. The molecular weight of zirconia is 123.22, the theoretical density is 5.89g/cm3, and the melting point is 2715°C.