KxNa1-xNbO3无铅压电陶瓷的常压烧结及其性能研究

以固相法合成了铌酸钾钠(KxNa1-xNbO3)粉体,采用常压烧结制备了铌酸钾钠无铅压电陶瓷,研究了粉体相组成,烧结温度,极化电压与陶瓷致密度、电学性能的关系。结果表明:当x=0.5,烧结温度为1050℃,极化电压为3kV/mm时,可制备出具有较好压电性能的铌酸钾钠压电陶瓷(相对密度为94%,压电常数d33=105pC/N,平面机电耦合系数kp=0.39,介质损耗tanδ=0.29,机械品质因数Qm=45,介电常数εr=720)。随着极化电场的增加,陶瓷压电性能提高,当极化电场E=3kV/mm时,极化基本达到饱和。

Research on Preparation and Electric Properties of KxNa1-xNbO3 Lead-Free Piezoelectric Ceramics

Potassium sodium niobate (KxNa1-xNbO3) powders were prepared by solid phase synthesis, and the KxNa1-xNbO3 ceramics were fabricated by pressureless sintering. The effect of the composition, sintering temperature and polarizing voltage on the phase composition of the powders and density, electrical properties of the ceramics were investigated. The results show that when x = 0.5, sintering temperature was 1050 oC and the polarization voltage was 3 kV/mm, KxNa1-xNbO3 ceramics with good piezoelectric properties (relative density reaches 94%, piezoelectric constant d33 = 105 pC/N, planar electromechanical coupling coefficient kp = 0.39, dielectric loss tanδ = 0.29, mechanical quality factor Qm = 45, and dielectric constant εr = 720) can be prepared. With the increasing polarization voltage, ceramic piezoelectric properties are increased, and the polarization basically reaches saturation when the polarization voltage E = 3 kV/mm.