Why is the strength of zirconia porcelain block so high？

The reason why zirconia porcelain pieces have such high strength is mainly attributed to the following aspects:

First, crystal structure and phase transition toughening

Polycrystalline structure: Zirconia ceramics belong to the polycrystalline structure of metal oxide ceramics, which has a high crystal hardness and strength.

Phase transition toughening: Zirconia in the process of heat or stress will undergo a transformation of crystal form, such as from monoclinic phase to tetragonal phase or cubic phase. This phase transition process absorbs energy, thereby increasing the toughness of the material and improving the ability to resist crack growth. This phase change toughening mechanism is one of the important sources of high strength of zirconia ceramics.

Second, grain size and microstructure

Grain size: Research shows that the strength of zirconia is inversely proportional to its grain size. The smaller the grain size and the larger the grain boundary area, the stronger the barrier effect of grain boundary on crack propagation, thus improving the strength and toughness of the material. Therefore, it is an effective way to improve the strength of zirconia ceramics to refine the grain by controlling the sintering process.

Microstructure: The microstructure of zirconia ceramics also has an important effect on its strength. Good microstructure can reduce internal defects and cracks, improve the density and uniformity of the material, and thus enhance the overall strength.

Third, the addition of stabilizer

Role of stabilizer: In order to further improve the strength and stability of zirconia ceramics, a certain amount of stabilizer (such as yttrium oxide Y2O3) is usually added. The stabilizer can inhibit the volume change of zirconia during the phase transformation process, prevent the internal stress and crack propagation caused by the volume change, and thus improve the overall strength and toughness of the material.

Fourth, the optimization of the preparation process

Sintering process: Appropriate parameters such as sintering temperature, time and pressure can promote the growth and densification of zirconia grains, reduce porosity, and improve the density and strength of materials.

Processing technology: The use of advanced processing technology (such as ceramic engraving machining) can reduce the defects and cracks generated during the processing process, and maintain the integrity and strength of the material.

Fifth, the performance of comprehensive performance

High strength and toughness: Due to the combined action of the above factors, zirconia ceramics show extremely high strength and toughness. Its bending strength can reach more than 1000MPa, and its fracture toughness is much higher than that of other traditional ceramic materials.

Wear resistance and corrosion resistance: In addition, zirconia ceramics also have good wear resistance and corrosion resistance, and can maintain long-term stable performance in harsh working environments.

In summary, the reason why zirconia porcelain block has such high strength is due to its unique crystal structure, small grain size, stabilizer addition, preparation process optimization and comprehensive performance of many factors such as the result of the joint action.