Alumina ceramic tube sintering is a key stage of ceramic preparation, and the sintering atmosphere has a great influence on the preparation of ceramic materials. Too high sintering temperature or too long holding time will promote crystal growth, so that the fine raw materials will develop into coarse grains at high temperature, and the amount of liquid phase will increase. This will not only decrease the strength, but also weaken the wear resistance. Of course, if the temperature is too low, the sintered body will not be dense, and the wear resistance of the product will not be good.

Production practice and a large number of studies show that: low porosity, high density alumina ceramics have excellent structural properties. High density means that the crystal grains in the ceramic body are tightly arranged, and it is not easy to form destructive breakthrough points when subjected to external loads or corrosive substances.

In order to obtain alumina ceramic materials with high wear resistance, not only should it be considered to have high density, flexural and compressive strength, but also to increase its hardness and fracture toughness, and these properties are in line with the obvious characteristics of alumina ceramics. The microstructure (closed porosity, grain size, distribution of glass phase, etc.) and its wear mechanism are closely related.

In order to prolong the service life of high purity alumina furnace tubes and reduce the losses caused by damages due to improper use, the following suggestions are hereby put forward for users' reference