uO掺杂(Ba0.7Ca0.3)TiO3-Ba(Zr0.2Ti0.8)O3无铅压电陶瓷的研究

In this paper 0.45(Ba0.7Ca0.3)TiO3-0.55Ba(Zr0.2Ti0.8)O3（BCZT45）based lead-free piezoelectric ceramics with different amount of CuO addictives were fabricated by sintering at different temperatures, and the effects of CuO-doping on microstructure, phase structure, piezoelectric and dielectric properties were studied. The X-ray diffraction (XRD) shows that Cu2+ ions diffused into the BCZT45 lattices and formed a solid solution with a single perovskite structure. Cu2+ ions partially substituted for Ti4+ and caused lattice distortion. The addition of CuO aid improved the sintering of BCZT ceramics, lowered sintering temperature and enhanced bulk density. With the addition of CuO, the curves of the temperature dependence of the relative dielectric constant were shifted to lower temperatures, showing that the rhombohedral-tetragonal (TR-T) and tetragonal-cubic (TC) phase transition temperatures both decreased. The piezoelectric constant (d33) increased with small amount of CuO addition, and decreased sharply with more addition. BCZT45 ceramics with 0.25 mol. % CuO aid exhibited the optimum properties: d33=340 pC/N, dielectric constant εr=3147, dielectric loss tanδ=0.025.