How to solve the problem of sintering and cracking of zirconia ceramics?

With the continuous development and progress of science and technology, zirconia ceramics have been widely used in various fields, so how to solve the problem of sintering and cracking of zirconia ceramics? Next, Pintejin ceramics will introduce to you.

Due to the high hardness of stabilized zirconia ceramics, it is generally used in a steel ball mill for ductile ink, pickling after the ductile ink, and then neutralized with water and dried.

The zirconia ceramics are formed by grouting, and the neutral slurry is prepared in the ceramic ball mill with the above materials. Powder (small and 0.05um), the purity is 99.5%.

Sintering: In a neutral or oxidizing atmosphere, sintering at 1800-1840 degrees, the phase transformation of zirconia ceramics has a large volume change, so as to absorb or release energy.

This may be the main reason for cracking. In addition, to solve the phase transition of zirconia, many of them are inhibited by doping. For example, YSZ or SSZ, which are often used in high-temperature fuel cells, are to dope a certain phase. , stable to room temperature.

Generally, Y oxides or other materials are doped to inhibit the phase transformation of zirconia ceramics. If you do not add inhibitors, cracking during sintering is inevitable.

Cracking during drying, please refer to the three stages of drying process: constant-speed drying, first-speed drying and second-speed drying. The constant velocity drying stage is the process of volatilization of water on the surface of the green body, and mass transfer in the gas-liquid two-phase through the liquid film, there is no concentration difference at each position.

The external conditions are the same, which is uniform drying; after the surface water is volatilized, the free water inside the green body is volatilized outward under the drive of capillary force, which is the first deceleration stage; the second deceleration stage is a small amount of free water and bound water. Stages of external emissions.

Therefore, the main reason for drying cracking is that the capillary force is greater than the strength of the green body itself.

The above is what Pintejin Ceramics brings to you. Pintejin Ceramics is a manufacturer specializing in the production and machining of ceramics, focusing on the machining of alumina ceramic parts and zirconia ceramics, and can process ceramic products according to your needs.