Application of response surface methodology (RSM) for optimization of sintering process for the preparation of magnesia partially stabilized zirconia (Mg-PSZ) using natural baddeleyite as starting material

In this work, instead of chemical pure zirconia, natural baddeleyite was used as starting material to prepare partially stabilized zirconia (PSZ) with magnesia as stabilizer. Response surface methodology (RSM) involving central composite design (CCD) was employed to optimize the sintering process for the preparation of magnesia partially stabilized zirconia (MgO-PSZ) with the aim of improving the relative density and bending strength of the materials. The interaction between three variables i.e. sintering temperature, holding time and heating rate was studied and modeled. The statistical analysis of the results showed that in the range studied, sintering temperature had a significant effect on relative density and bending strength. The optimum combination predicted by RSM was experimentally confirmed, whereby almost complete densification with the relative density 99.44% was obtained at a 3 °C/min cooling rate.