Effect of CuBi2O4 additive on dielectric, ferroelectric, and piezoelectric properties of BCTZ lead free ceramics sintered at low temperature

摘要

The influence of CuBi₂O₄ addition on sintering temperature, structural, dielectric and piezoelectric properties of (Ba, Ca)(Ti, Zr)O₃ BCTZ ceramics prepared by the direct solid-state reaction were investigated. The X ray diffraction (XRD) data showed a single phase perovskite structure with morphotropic phase for all samples. The scanning electron microscopy observation showed the formation of glass phase in BCTZ doped compositions, which explain the reducing in sintering temperatures. The CuBi₂O₄ addition decrease the rhomboedral-tetragonal transition temperature and slightly increase Curie temperature. Ferroelectric measurements show that remanent polarisation (P _r), and the coercive field of ceramics firstly increases and then decreases with further increasing the CuBi2O4 content. The dielectric behavior of all samples exhibited diffuse phase transition behaviour. Samples of the BCTZ ceramics modified with 0.08% of CuBi₂O₄ exhibited the highest density (5.39 g/cm^{3), the highest dielectric constant (ε_r=10566.) and the best piezoelectric constant (d₃₃ = 320 pC/N)}