5D-4 Piezoelectric Properties of Nd and V Co-Substituted Bi4Ti3O12 Ceramics for Resonator Applications

The temperature dependence of piezoelectric properties of Nd and V co-substituted bismuth titanate ceramics, (Bi_4-y,Nd_y )_1-(x/12)(Ti_3-x,V_x)O₁₂ [BNTV(x,y) (x = 0.01, y = 0.75), BNTV(0.01, 0.75)] ceramic was investigated for ceramic resonator applications, focusing on temperature dependences of resonance frequency, TC-f mechanical quality factors, Q _m, and electrical quality factors, Q_emax. The TC-f of random oriented BNTV(0.01, 0.75) in (33) mode was -77.4 ppm/degC, which value is a little large for the practical requirement of ceramic resonator. Effects of grain orientation in BNTV(0.01, 0.75) ceramic on the piezoelectric properties were also studied using the hot-forging (HF) method. The excellent piezoelectric properties of both high Q_m (~2230) and Q_emax (~37) were obtained in the HF-BNTV(0.01, 0.75) ceramic. Furthermore, the grain oriented one showed the smaller TC-f value of -59.7 ppm/degC. The HF-BNTV(0.01, 0.75) ceramic is considered to be superior candidates for lead-free piezoelectric application of ceramic resonators