A Brief Introduction Of 10 Sintering Processes For Alumina Ceramics-3 4

3. Hot isostatic

Hot isostatic sintering is the process of applying pressure in all directions of the ceramic body at the same time to reduce the sintering temperature of the ceramic body, and the ceramic structure is uniform and the performance is good.Although hot isostatic sintering can successfully reduce the sintering temperature of ceramics and obtain objects with complex shapes, hot isostatic sintering needs to be done in advance to encapsulate or presintered the blank body, and the pressure conditions will be relatively harsh.

4.Ultra- high pressure sintering

Ultra-high pressure sintering means sintering under great pressure. Due to the great pressure, the atomic diffusion is inhibited and the nucleation barrier is relatively small, high density (& GT;98%) high purity alumina ceramics.In the process of ultra-high pressure sintering, the presence of pressure increases the vacancy and atomic diffusion rate in the particle, and the pressure and surface energy together serve as the driving force of sintering, enhancing the diffusion effect.Ultra-high pressure sintering usually only needs to be carried out at relatively low temperature, and the abnormal growth of grains is inhibited, so that high-purity alumina ceramics with high densification degree, fine grain size and uniform distribution can be obtained.