alumina ceramic products sintering process
Sintering is actually a process in the production of alumina ceramics, but there are different changes before, during and after sintering.
First of all, before sintering, the relevant control of temperature is more important. Due to the continuous rise of temperature, the billet will shrink, but the strength and density are not obvious in the whole change, and in the microstructure, the grain size will not change, but the billet is relatively easy to crack, mainly because of water Components and binders are completely eliminated, so the temperature should be controlled in place at the rising speed.
Secondly, in the middle stage of sintering, the temperature will change a little, the volume will contract constantly, and the density and strength will change a lot. Although in the microstructure, the grain size will not change obviously, in fact, the grains are not only coarsened each other, and the pores will gradually reduce a lot. In this stage, the billet will realize that Because of the volume shrinkage caused by sintering, it is very easy to deform and crack the billet.
At last, in the later stage of sintering, the temperature rises faster, and all changes will become more and more obvious. Only the change of strength and density will not be obvious. If it is in the microstructure, the change of the whole grain size will be very obvious, and the pores will be smaller and smaller, which are not connected with each other, and more isolated pores will be formed, and some pores will be direct Remaining in the interior of the grain.