摘要
高熵陶瓷是近年来在高熵合金基础上逐渐发展起来的一种新的陶瓷材料体系,它的出现为开发具有优异性能的非金属材料提供了新的理念和路线。本研究采用固相烧结法制备A位等摩尔比的钙钛矿型高熵氧化物陶瓷(La_(0.2)Li_(0.2)Ba_(0.2)Sr_(0.2)Ca_(0.2))TiO_(3),并探索了烧结温度对高熵陶瓷的物相结构及电学性能的影响。结果表明,陶瓷经现有温度烧结后均表现为立方钙钛矿结构,并且展现出良好的绝缘性,其漏电流密度在10^(-8)~10^(-6)A/cm^(2)数量级。尽管随烧结温度的升高,陶瓷的晶粒尺寸不断增大,但该显微结构与介电性能的关联并不显著。当烧结温度为1350℃时,介电常数出现最大值,在频率为100 Hz下,介电常数约为230。同时,该高熵陶瓷的介电温谱表明陶瓷存在弛豫行为,其介电常数的弛豫峰随着频率的增加向高温方向移动。
High entropy ceramic is a kind of ceramic developed based on the high entropy alloy in recent years.The appearance of high entropy ceramics provides a new concept and route for developing non-metallic materials with excellent properties.In present work,a series of high-entropy ceramics with a molar ratio of A site—(La_(0.2)Li_(0.2)Ba_(0.2)Sr_(0.2)Ca_(0.2))TiO_(3)were successfully synthesized by solid state reaction.The effects of sintering temperature on phase,microstructure and electric properties were investigated.Results show that the high-entropy ceramics sintered at current temperatures are of cubic perovskite structure,and exhibit excellent insulation,with low leakage current density of J value around 10^(-8)-10^(-6)A/cm^(2).Although the grain size increases with the increase of sintering temperature,the correlation between microstructure and dielectric properties of(La_(0.2)Li_(0.2)Ba_(0.2)Sr_(0.2)Ca_(0.2))TiO_(3)ceramics is not significant.The dielectric constant reaches its maximum value at 1350℃,with the value of 230 at the frequency of 100 Hz.Meanwhile,this high-entropy ceramic has relaxation behavior,and the relaxation peak of the permittivity moves towards high temperature with the increase of frequency.
作者
张晓燕
刘馨玥
闫金华
谷耀行
齐西伟
ZHANG Xiaoyan;LIU Xinyue;YAN Jinhua;GU Yaohang;QI Xiwei(School of Materials Science and Engineering,Northeastern University,Shenyang 110819,China;School of Resources and Materials,Northeastern University at Qinhuangdao Branch,Qinhuangdao 066004,China;Key Laboratory of Dielectric and Electrolyte Functional Material,Qinhuangdao 066004,China;College of Metallurgy and Energy,North China of Science and Technology,Tangshan 063210,China)
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
2021年第4期379-385,共7页
Journal of Inorganic Materials
基金
国家自然科学基金(51972048)。
关键词
高熵陶瓷
钙钛矿
介电性能
high-entropy ceramics
perovskite
dielectric property
