Bi_(0.5)(Na_(0.8)K_(0.2-x)Li_x)_(0.5)TiO_3无铅压电陶瓷的制备及性能研究

Preparation and properties of BNKLT lead-free piezoelectric ceramics

采用固相反应方法制备Bi0.5(Na0.8K0.2-x Lix)0.5TiO3无铅压电陶瓷。研究该体系陶瓷的组成变化及烧结工艺对压电陶瓷的相组成、显微结构及电性能的影响。结果表明,混合原料的平均粒径在2μm左右,粒度呈正态分布。热分析确定了混合原料的合成温度为900℃。XRD分析表明,900℃预烧温度下,合成粉体为ABO3的钙钛矿结构,且为铁电四方相结构。SEM表明,组成在x=0.06,烧结温度为1 160℃时,能够获得烧结良好且致密度较高的陶瓷,该组成的陶瓷的电性能具有最佳值,εT33/ε0=1 160、tanδ=0.029、d33=195pC/N、kp=0.407。

Bi0.5(Na0.8K0.2-xLix)0.5TiO3lead-free piezoelectric ceramics were prepared by solid state reaction method.The effect of composition and sintering process on the phase,microstructure and electric-properties were studied.The results show that the average grain sizes of the mixed power are about 2μm.The calcination temperature of 900 ℃is determined by thermal analysis.By XRD detecting,the calcinated powder are ABO3 perovskite structures and all ferroelectric tetragonal phase.By SEM,the good sintering ceramics with a high density are obtained for the ceramic with x=0.06 and sintering temperature of 1 160 ℃.The excellent electric properties ofεT33/ε0=1 160,tanδ=0.029,d33=160pC/N,kp=0.407 are tested at the composition.