1. Corundum ceramic material has the characteristics of high temperature resistance, high strength, creep resistance, abrasion resistance, good insulation, light weight and so on. It is an ideal structural ceramic material, which has been widely used in many industrial sectors. As a new type of structural ceramic material, it has been applied to the parts of high-power generator, precision machining parts, components in the field of electronic technology and other new scientific and technological fields. The application in these new scientific and technological fields has put forward higher requirements for the performance of corundum ceramic materials. Due to the brittleness of corundum ceramic materials, In order to overcome the brittleness of ceramic materials and improve the safety and reliability, its toughening is one of the important issues faced by contemporary ceramic scientists. A variety of toughening mechanisms have been proposed for ceramic materials. The more mature and widely used toughening methods are ZrO2 toughening and fiber toughening. At present, there are successful cases in the Chinese market. ZTA produced by Jingcheng Special porcelain adopts isostatic pressing embryo, tunnel resistance kiln firing toughened alumina ceramics and ZTA special ceramics.
2, we all know that natural alumina is corundum, Mo hardness is 9, cubic zirconia Mo hardness is 8.5, but from the point of view of the use of industrial wear-resistant ceramics, not the higher the hardness is better, but also look at the toughness of ceramics, hardness and toughness are high, can be said to be the best wear-resistant ceramics. It is not that zirconia ceramics are inferior to alumina ceramics. The lattice phase of zirconia ceramics is very stable at high temperature, and the lattice of zirconia ceramics will be damaged when reduced to normal temperature. So at room temperature, in terms of pure alumina and pure zirconia, alumina has a higher hardness and is theoretically more wear-resistant. But alumina wear-resistant ceramic is a mixture, it is artificial ingredients and then dry pressed, sintered 1680℃ to become, not pure corundum. Therefore, to see the alumina content of ceramics, some manufacturers have 85% alumina ceramics, 92% alumina ceramics, 95% alumina ceramics, 99% alumina ceramics and other ceramics, Jingcheng wear-resistant ceramics in this wear-resistant ceramic industry research is very deep and professional, Jingcheng production of wear-resistant ceramics Rockwell hardness of HRA82-90, Fracture toughness KIC≥7.5Mpa.m1/2, hardness second only to diamond.
3, ZTA toughening alumina ceramics is to increase a certain on the basis of the alumina zirconia ceramics ingredients, abrasion resistance and toughness between alumina and zirconia ceramics, because the price of zirconia ceramic is higher, the user to invest is bigger, manufacturer of most used mainly European and American companies and Australia BHP billiton group.
4. The lattice of zirconia ceramics is stable at high temperature, but the lattice phase is damaged at normal temperature. Therefore, 5.6% stabilizer (rare earth, etc.) must be added to 94.4% zirconia to reach a stable state at normal temperature, and the powder is dry pressed and sintered at 1560℃, so the hardness and toughness will exceed 99% alumina ceramics. Its wear resistance and impact resistance is more than 99% alumina ceramics. If no stabilizer is added, ceramics are easy to crack, so zirconia ball as an abrasive material, because it has great hardness and toughness.
