Sintering Kinetics of Plasma-Sprayed Zirconia TBCs

The sintering of free-standing plasma sprayed TBCs has been modeled, based on variational principles of free energy minimization and comparisons are made with experimental results. Predictions of through-thickness shrinkage and changing pore surface area are compared with the experimental data obtained by dilatometry and BET analysis, respectively. The sensitivity of the predictions to initial pore architecture and material properties is assessed. The model can be used to predict the evolution of the contact area between overlying splats. This is in turn related to the through-thickness thermal conductivity, using a previously developed analytical model (I.O. Golosnoy, et al. J. Therm. Spray Technol., 2005, 14(2), p 205-214).