Complex Analysis of High-Temperature Piezoelectric Ceramics Combining Sr and Nb Co-Doped Bi4Ti3O12

The Nb-modified Bi4Ti3O12 (BIT + xmol% Nb2O5) layer structured piezoelectric ceramic is obtained by the solid-phase method.The study showed that as the content of Nb2O was increased, the ab-plane-oriented grains were gradually increased, and the grain size became more refined and uniform.The introduction of Nb2O5 has significantly reduced the electrical conductivity and dielectric loss of the BIT series ceramics and increased the relative density as well as the piezoelectric and electromechanical properties of ceramics.The results indicate that all samples are single bismuth layer structured phase ceramics.The proper introduction of Sr makes the grain size of BTNO ceramics refined and uniform, presenting dielectric dispersion, and improves its piezoelectric, electromechanical, and ferroelectric properties.When x = 0.50, the sample has the optimal performance as the following: relative density ρ = 98.8%, piezoelectric constant d33 = 22 p C/N, planar electromechanical coupling factor kp = 9.5%, mechanical quality factor Qm = 4462, remnant polarization Pr = 13.01 μ C/cm 2 , Curie temperature Tc = 62℃.In addition, the research on its dielectric properties and thermal stability has suggested that the material (x = 0.50) has excellent piezoelectric stability and is suitable for the preparation of high-temperature and high-frequency piezoelectric devices.