Selection of optimal sintering temperature of K0.5Na0.5NbO3 ceramics for electromechanical applications

Abstract

This paper has considered the selection of the optimal processing parameter (sintering temperature) leading to best possible properties of K0.5Na0.5NbO3 (KNN) for electromechanical applications. Vital piezoelectric properties for such applications include the piezoelectric coupling coefficient (kp), piezoelectric coefficient (d31), Curie temperature (Tc), remanent polarization (Pr), coercive field (Ec), density (ρ), elastic compliance (S11E and S12E) and dielectric loss (tan δ). The weights and priority of these physical properties for KNN are calculated using the modified digital logic (MDL) method. The priority order of these properties used for the selection of optimal processing parameters is as d31>tan δ>S11E=S12E>Tc=Pr>ρ>kp>Ec. The weights obtained using MDL are further incorporated with analytic hierarchy process (AHP) and VlseKriterijumska Optimisacija I Kompromisno Resenje (VIKOR) in order to determine the optimal sintering temperature for KNN. Both methods suggest that 1080 °C and 1120 °C are the most and least desirable sintering temperatures, respectively. Finally, sensitivity analysis is performed for the robustness of our results and prediction of most influential parameter in terms of sensitivity. tan δ is found to be the most sensitive property for alteration in the present ranking