CuO掺杂的(Na_(0.66)K_(0.34))NbO_3无铅压电陶瓷性能研究  

A study on CuO doped(Na_(0.66)K_(0.34))NbO_3 lead-free piezoceramics

作　　者：臧国忠[1] 门秀婷[1] 郭晴[1] 刘燕燕[1] 王燕[1] 

机构地区：[1]聊城大学材料科学与工程学院,山东聊城252059

出　　处：《功能材料》2011年第B04期310-313,共4页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(50802038)

摘　　要：采用传统工艺制备了CuO掺杂的无铅压电陶瓷(Na0.66K0.34)NbO3,研究了CuO掺杂对其压电、介电、铁电等性质的影响。实验结果显示,CuO掺杂促进了晶粒生长,降低了样品的烧结温度,适量掺杂能够显著提高陶瓷样品的密度。当掺杂量为0.5%(摩尔分数)时,样品的密度为4.26g/cm3,品质因子Qm提高到400,介电损耗tanδ降低至0.8%。实验结果还显示,CuO掺杂使得陶瓷变"硬",起到硬性添加剂的作用。随着CuO掺杂量的增加,样品的居里点(TC)、正交-四方相变温度(TT-O)、压电常数d33以及机电耦合系数kp均明显降低,而矫顽场显著增加。对于不掺杂的(Na0.66K0.34)NbO3陶瓷,其d33高达107pC/N,该陶瓷优异的压电性能表明,除了具有准同型相界结构的(Na0.5K0.5)NbO3外,(Na0.66K0.34)NbO3也是一种具有研究潜力的无铅压电陶瓷组分。（Na0.66 Ko. 34 ）NbO3 ceramics were prepared by conventional oxide solid solution technique and the effect of CuO on the piezoelectric, dielectric and ferroelectric properties were investigated. The experimental results showed that the doping of CuO facilitated the grain growth and lowered the sintering temperature. By proper doping of 0.5 mol% CuO, the sample density and mechanical quality factor Qm was improved to 4.26g/ cm3 and 400, respectively, the dielectric loss was depressed sharply from about 4.3O//oo to 0.8%. The experimen- tal results also showed that the doping of CuO has a ＂hard＂ effect on the properties of （Na0.66 K0.34 ）NbO3 ceram- ics. The Curie temperature （Tc）, orthorhombic-tetragonal phase transition temperature （Tτ-o）, piezoelectric coefficient d33 and electromechanical coupling coefficient kp decreased, whereas the coercive field Ec increased with increasing CuO content. The good property of d33=107pC/N for the sample without CuO suggests that the composition of （Na0.66 K0.34 ）NhO3 is another promising lead-free candidate for investigation besides （Na0.5 K0. 5 ） NbO3 system.

关 键 词：无铅压电陶瓷 KNN 铁电性能 居里温度 

分 类 号：TM22[一般工业技术—材料科学与工程]