CAJ | 학술논문

通过对克劳修斯-莫索蒂方程的近似,分析了钙钛矿结构微波介质陶瓷频率温度系数(τf)的主要影响因素,发现改变材料介电响应中离子位移极化和电子位移极化的比例,可调节频率温度系数的正负与大小.通过电子结构计算和容忍因子分析,预测引入(Zn1/3Nb2/3)4+对具有正温度系数的CaTiO3进行B位取代将提高材料电子极化响应比例,调节τf 由正变负.采用偏铌酸盐为前驱体,通过固相反应法合成了Ca[(Zn1/3Nb2/3)xTi(1?x)]O3钙钛矿结构陶瓷,并对其进行结构分析和性能测试,实验结果与理论分析一致,获得了具有近零频率温度系数的Ca[(Zn1/3Nb2/3)0.7Ti0.3]O3介质陶瓷材料.
통과대극로수사-막색체방정적근사,분석료개태광결구미파개질도자빈솔온도계수(τf)적주요영향인소,발현개변재료개전향응중리자위이겁화화전자위이겁화적비례,가조절빈솔온도계수적정부여대소.통과전자결구계산화용인인자분석,예측인입(Zn1/3Nb2/3)4+대구유정온도계수적CaTiO3진행B위취대장제고재료전자겁화향응비례,조절τf 유정변부.채용편니산염위전구체,통과고상반응법합성료Ca[(Zn1/3Nb2/3)xTi(1?x)]O3개태광결구도자,병대기진행결구분석화성능측시,실험결과여이론분석일치,획득료구유근령빈솔온도계수적Ca[(Zn1/3Nb2/3)0.7Ti0.3]O3개질도자재료.
The determinants of resonant frequency temperature coefficient (τf) have been analyzed by the approximate treatment of Clausius-Mossotti equation. It is suggested that the value ofτf can be adjusted by changing the contribution proportion of ionic polarization or electronic polarization for the dielectric constant. Results of electronic structure calculation and tolerance factor analysis show that B-site substitution of CaTiO3 with (Zn1/3Nb2/3)4+could turn the value ofτf from positive to negative, by enhancing the covalency in the BO6 octahedron and improving the contribution proportion of electronic polarization. Ca[(Zn1/3Nb2/3)xTi(1?x)]O3 dielectric ceramics were prepared by solid-state reaction method with niobate as precursor. Results of structure analysis and property measurement conform to the theoretical analysis. The Ca[(Zn1/3Nb2/3)0.7Ti0.3]O3 dielectric ceramic with near-zeroτf was obtained.