Low-temperature sintering of alkaline niobate based piezoelectric ceramics using sintering aids

概要

論文の詳細を見る
Three kinds of sintering aids, LiBiO_2, CuBi_2O_4 and LiBO_2, were selected as sintering aids for the low temperature sintering of (Li_<0.04>K_<0.52>Na_<0.44>)(Nb_<0.84>Ta_<0.1>Sb_<0.06>)O_3 (LF4) ceramics and the effects of these compounds on the sintering behavior of the LF4 ceramics was investigated. The addition of LiBiO_2 decreased the sintering temperature of LF4 about 100℃ but the effect was limited and the broadening of XRD peaks due to the degradation of crystallinity was observed. The CuBi_2O_4 was also effective to decrease the sintering temperature of LF4 ceramics but a secondary phase was formed when a large amount of CuBi_2O_4 was added. The addition of a small amount of LiBO_2 was very effective to decrease the sintering temperature of LF4 ceramics. By optimizing the sintering conditions, ceramics with the relative density of 95% were obtained at 950℃ which was lower than the melting point of Ag. Li ions in LiBO_2 were incorporated into the LF4 lattices, giving rise to the degradation of piezoelectric properties through the change of crystalline phase. The addition of excess Na with LiBO_2 restricted the incorporation of Li ions into the lattice. Ceramics sintered at 950℃ showed the relative permittivity of 738 and the d_<33> constant of 138pC/N at room temperature.
社団法人日本セラミックス協会の論文
2008-11-01