Low-Temperature Sintering of (Bi,Na)0.83Ba0.17TiO3--0.2 wt % CuO Piezoelectric Ceramics from Nanopowders

Using (Bi 0.5 Na 0.5 ) 0.83 Ba 0.17 TiO 3 nanopowders synthesized by an oxalate precursor route, 0.2-wt %-CuO-doped ceramics can be sintered at a low temperature of 880 °C. The shrinkage rate is 16.5%, the relative density $D_{\text{r}}$ is 98%, the relative dielectric constant $\varepsilon^{\text{T}}_{33}/\varepsilon_{0}$ (1 kHz) is 705, the loss $\tan \delta$ (1 kHz) is 2.50%, the electromechanical coupling factor $k_{\text{p}}$ is 13.6%, and the piezoelectric charge coefficient $d_{33}$ is 105 pC/N.