1. Creep is the first. The structural parts of alumina ceramics under high temperature, when subjected to external force, will continuously and slowly appear plastic deformation due to the increase of time, so we can call it creep . However, when the creep of alumina ceramic structural parts is related to stress or temperature, when the stress increases or the temperature continues to increase, the creep rate will continue to increase.
2. Graphitization and spheroidization, under the action of high temperature, the cementite contained in the structural parts of alumina ceramics will gather or migrate due to the large energy obtained, and will be transformed into coarse grains Cementite is intercalated in ferrite, and cementite will also gradually change from flaky to spherical, we can call it spheroidization. Because graphite is very low in strength, and it is mainly in the form of flakes, resulting in a great reduction in the strength of the material, and the brittleness will also increase, so it can be called graphitization.
3. The performance of thermal fatigue. If the structural parts of alumina ceramics are alternated between cold and hot for a long time, the changes in the internal temperature difference of the material will appear due to the effect of thermal stress. Rupture phenomenon. Therefore, when working under the condition of fluctuating temperature, the fatigue performance of its structural parts should be considered.
What happens to the structural parts of alumina ceramics under high temperature?
2020 05/25