摘要
采用固相法制备Na_(0.25)K_(0.25)Bi_(2.5–x)Nd_xNb_2O_9(NKBN–xNd^(3+),0≤x≤0.40,x为摩尔分数)铋层状无铅压电陶瓷,研究了不同Nd^(3+)掺杂量对NKBN–x Nd陶瓷显微结构、电学性能的影响及NKBN–0.20Nd^(3+)陶瓷高温下的电导行为。结果表明:所有样品均为单一的铋层状结构;当Nd^(3+)的掺杂量x为0.02时,样品的晶粒尺寸减小并趋于均匀,致密度提高;适量的Nd^(3+)掺杂能降低样品的介电损耗,提高NKBN陶瓷的压电常数d33。NKBN–0.20Nd^(3+)陶瓷样品的电学性能最佳:压电常数d_(33)=24 p C/N,机械品质因数Q_m=2 449,tanδ=0.40%,2P_r=1.11μC/cm^2。NKBN–0.20Nd^(3+)样品的阻抗谱表明:在高温区域陶瓷的晶粒对电传导起主要作用,当温度高于600℃时,样品主要表现为本征电导,NKBN–0.20Nd^(3+)和NKBN的电导活化能分别为1.85和1.64 e V。
Na0.25K0.25Bi2.5-xNdxNb209（NKBN-xNd, 0≤x≤0.40） bismuth layered structure lead-free piezoelectric ceramics were prepared by a solid-state reaction method. Effect of Nd3＋ doping amount on the microstructure, electrical properties of NKBN-xNd ceramics was investigated. The high-temperature conductive behavior of NKBN-0.20Nd ceramic was analyzed. The results show that all the samples possess a single bismuth layered structure. When the Nd3＋ doping content x is 0.02, the average grain size decreases, the grain size distribution becomes uniform and the density increases. A appropriate content of Nd^3＋ leads to the decrease of tand and the increase of d33. The NKBN-0.20Nd sample presents the optimal piezoelectric performance, i.e., d33=24 pC/N, Qm=2 449, tand=0.40%, 2Pr=1.11 μC/cm2. According to the impedance spectra of the NKBN-0.20Nd sample, the grain interior makes a major contribution to the electrical conduction process at a high temperature. At 〉 600 ℃, the intrinsic conduction plays a dominant role in the samples. The calculated activation energy of NKBN-0.20Nd and NKBN samples is 1.85 and 1.64 eV, respectively.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2017年第3期346-353,共8页
Journal of The Chinese Ceramic Society
基金
国家自然科学基金(51562014
51262009)
江西省自然科学基金(20133ACB20002
20142BAB216009)
江西省高等学校"先进陶瓷材料"科技创新团队
江西省教育厅科技项目(GJJ150911
GJJ150931
GJJ150933)资助
关键词
铋层状
压电陶瓷
RAMAN光谱
阻抗谱
bismuth layer-structured
piezoelectric ceramics
Raman spectroscopy
complex impedance spectrum
