Specific analysis of alumina ceramic toughening technology research
For alumina ceramics, it has a very high temperature resistance, and has many advantages such as corrosion resistance and wear resistance. It is also an industrial ceramic material with a relatively large production volume in the world. For alumina ceramics, it is remarkable in many applications such as machinery, electronics, automobiles, and instrumentation, chemical, chemical fiber, and so on.
For the application of alumina ceramics, it is also because of its own brittleness, it has restrictions on its application. This is mainly determined by the structural characteristics of our materials. For chemical bonds in ceramic materials, it is mainly based on covalent bonds and ionic bonds. For both types of chemical bonds, they all have relatively strong directionality, and there is a relatively high strength of bonding. It will lead to plastic deformation, brittleness and its crack sensitivity.
It is for these reasons that we are also paying more attention to research to improve the toughness of alumina ceramics. In the recent words, we will actually add some reinforcing materials such as particles, whiskers, and fibers to the ceramics, so that the toughness of our ceramics can be greatly improved, and also for its strength and modulus. There is a certain improvement.
For the method of toughening alumina ceramics, the main thing is that there is grain toughening, and there is whisker toughening. For its toughening principle, it is actually very simple. The main thing is that its reinforcement and its surrounding matrix can produce a residual stress field, which has a significant effect on hindering crack expansion and enhancing toughness.
In the following, regarding the toughening principle of alumina ceramics, we should pay attention to the pinning effect of its microcracks, as well as its crack tip and its tail effect; in addition, its reinforcement will cause cracks. The stress at the tip is relaxed, which has certain advantages in slowing the crack propagation. From the above aspects, it is the toughening principle of our alumina ceramics.