Effect of MnO2 on the Piezoelectric Properties of (1-x)(Na0.5K0.5)NbO3–xBaTiO3 Ceramics

Abstract

(Na_0.5K_0.5)NbO₃ (NKN) and BaTiO₃ (BT) ceramics form a homogeneous solid solution. The relative density of the (1-x)NKN–xBT solid solutions significantly decreased when x≤0.07. Although the relative density of the 0.95NKN–0.05BT ceramic was very low, it had a high d ₃₃ value of 134 pC/N. MnO₂ was added to improve the piezoelectric properties of the 0.95NKN–0.05BT ceramics by enhancing their sinterability. The addition of MnO₂ increased the density of the specimens, as well as improving the piezoelectric properties. The 0.9 mol % MnO₂ added 0.95NKN–0.05BT ceramics showed the good piezoelectric properties of k _p=0.31, d ₃₃=194 pC/N and ε ₃ ^T/ ε ₀ = 800.