Model-supported optimisation of the sinter-HIP process

A sinter hot isostatic pressing (HIP) model is introduced for the
material Al2O3 in which the final densification simultaneously includes
defining the density development, grain growth and defect size
reduction. The dependencies of these processes which influence each
other are simulated in a computer program and the model calculations
are compared with the experimental results. For the selected
combinations of processing and microstructural parameters, the
individually dominating mechanisms and the achievable microstructural
conditions can be thus identified. The results make conclusions
possible about the size of the defects, which can be effectively
reduced by the given processing and by optimised sintering kinetics.
With a new type of diagram (GDDT diagram), it is possible to simply
represent the complex interactions between the processing parameters
and the microstructure development. This allows the determination of
optimal processing at given appropriate conditions, which thus allow
the sintering and HIP processes to be optimally planned.