摘要
采用固相法制备Bi1.5-xEuxMgNb1.5O7(x=0、0.1、0.2、0.3、0.4、0.5和0.6)陶瓷。采用X线衍射仪(XRD)、扫描电子显微镜(SEM)和阻抗分析仪分别对陶瓷的相结构、显微结构和介电性能进行表征。结果表明:当Eu3+取代量(x)较小(x≤0.5)时,所有组分的陶瓷样品均保持单一的焦绿石相;当x=0.6时,样品出现少量的EuNbO4杂相。随着Eu3+取代量的增加,陶瓷的介电常数逐渐减小,介电损耗先减小后增大,温度系数显著增大。当x=0.5时,1 MHz下测得的介电常数为96,介电损耗为3.8×10-4,温度系数变成-12×10-6℃-1。因此,通过适当的Eu3+取代可以获得适用于Ⅰ类多层陶瓷电容器性能优异的介质材料。
The Bi1.5-xEuxMgNb1.5O7 （ x = 0,0. 1,0. 2,0. 3,0.4,0.5,0. 6 ） ceramics were synthesized by conventional solid-state reaction method. The phase structure, the mierostructure and the dielectric properties were investigated by X-ray diffraction （XRD）, scanning electron microscope （SEM） and impedance analysis meter. The results showed that the Bi1.5-x Eux MgNb1.5 O7 ceramics with single pyrochlore phase could be obtained with small amount of Eu^3 ＋ substitution （x ≤ 0. 5 ） while another phase EuNbQ appeared for x = 0. 6. As Eu^3＋ content increased, the dielectric constant decreased gradually while the dielectric loss decreased at first, and then increased. Especially the temperature coefficient of dielectric constant was enhanced pronouncedly. The dielectric constant was 96, the dielectric loss was 3.8 × 10 ^-4 and the temperature coefficient was - 12 × 10^-6 ℃^ -1 for x = 0. 5 at 1 MHz. Hence, dielectric materials with excellent properties,which were suitable for Class I multilayer ceramic capacitors, could be achieved by proper Eu3 ＋ substitution.
出处
《南京工业大学学报（自然科学版）》
CAS
北大核心
2013年第4期12-16,共5页
Journal of Nanjing Tech University(Natural Science Edition)
基金
江苏高校优势学科建设工程(PAPD)
