溶胶-凝胶法制备Na_(0.5)Bi_(0.5)TiO_3-K_(0.5)Bi_(0.5)TiO_3体系无铅压电陶瓷的研究(英文)

Study on the Properties of Na_(0.5)Bi_(0.5)TiO_3-K_(0.5)Bi_(0.5)TiO_3 System Piezoelectric Ceramic Prepared by Sol-gel Method

采用溶胶-凝胶法制备(1-x)Na0.5Bi0.5TiO3-xK0.5Bi0.5TiO3体系无铅压电陶瓷。XRD分析表明,用溶胶-凝胶法可以在650℃下合成具有钙钛矿结构的(1-x)Na0.5Bi0.5TiO3-xK0.5Bi0.5TiO3粉体,且在x=0.18～0.30之间存在三方-四方准同型相界(MPB)。陶瓷的压电性能参数表明,该体系在MPB组成范围内具有最佳的压电性能:x=0.30时,压电常数d33达到最大值(d33=150pC.N-1),平面机电耦合系数kp与介电常数ε3T3/ε0均在x=0.26时达到最大值,分别为36.7%和1107。

In this paper,Sol-gel method was employed to prepare the（1-x）Na0.5Bi0.5TiO3-x K0.5Bi0.5TiO3 system lead-free piezoelectric ceramics.XRD results revealed that pure perovskite-type crystal structure of（1-x）Na0.5Bi0.5TiO3-x K0.5Bi0.5TiO3 powders can be synthesized by Sol-gel method calcined at 650 ℃,and the morphotropic phase boundary（MPB）with rhombohedral and tetragonal crystalline structure co-existed compositions was identified in the range of 0.18 to 0.30 of x concentration.In the MPB composition,the piezoelectric constant d33 reaches maximum 150 pC/N at x= 0.30,and when x equals to 0.26,electromechanical coupling factor kp and dielectric constant ε33^T/ε0 reach the maximum value which are 36.7% and 1107,respectively.