【摘要】 研究Li部分取代K对铌酸钾钠(KNN)无铅压电陶瓷性能的影响,选用(Na0.5K0.5-xLix)Nb O3(NKLxN)的配方,通过固相法制备出优良性能的陶瓷样品;运用XRD、SEM研究不同Li含量陶瓷样品的相结构及显微组织;通过压电介电性能测试,确定Li取代K的最佳含量.结果表明,当Li的含量x=0.065时,其d33=205p C/N,kp=46.1%,εr=998,tanδ=0.047,TD=485℃.该NKLxN陶瓷性能优良,在高温压电陶瓷传感器、换能器等方面可能取代铅基压电陶瓷.更多还原

【Abstract】 Effects of the process of K substituted partly by Li on the microstructure,dielectric andpiezoelectric properties of KNN-base lead-free piezoelectric ceramics were investigated.(Na0.5K0.5-xLix)Nb O3(NKLxN) lead- free piezoelectric ceramics were synthesized by conventional mixed- oxide method.Themicrostructure,phase structure and electrical properties were investigated as a function of Li addition,theoptimum by Li for K were determined via evaluation of the piezoelectric and dielectric properties of theresulting ceramics. The results show that the piezoelectric coefficient(d33),electromechanical couplingcoefficient(kp)reaches to peak values,205 p C/N,46.1% and εr=998,tanδ=0.047,TD=485 ℃ for the sample ofx=0.065. The combination of high transition temperature,high piezoelectric performances makes the NKLxNceramics prepared with the given process a very good candidate for replacing the lead- base piezoelectricceramics in high-temperature piezoelectric sensors and transducers,etc.更多还原