Microscopic sintering behavior in compacts formed by pressing ceramic granules is examined to develop a constitutive model for analysis of macroscopic deformation. Spray-dried alumina granules are compacted by CIPing and fired at various temperatures. The internal structure composed of fractured and unfractured granules, and large crack-like cavities caused by their inhomogeneous shrinkage during sintering are observed. The macroscopic sintering rate becomes slow because of the formation of the large cavities. A basic constitutive equation for sintering of ceramic powder compacts is proposed, with the grain boundary diffusion and the grain growth taken into account. The relationship between the change in the microstructure and the shrinkage rate of the powder compacts is modelled using the basic constitutive equation. The constitutive model is applied to the finite element analysis to predict the shape change of the compacts during sintering. The calculated results show good agreement with the experimental results.
|Number of pages||7|
|Journal||Nihon Kikai Gakkai Ronbunshu, A Hen/Transactions of the Japan Society of Mechanical Engineers, Part A|
|Publication status||Published - Jan 1 1998|
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Mechanics of Materials
- Mechanical Engineering