摘要
采用固态反应法成功制备出高熵(La_(0.2)Ho_(0.2)Er_(0.2)Y_(0.2)Yb_(0.2))NbO4陶瓷,利用X射线衍射仪、扫描电子显微镜、热膨胀计和热分析仪对比研究了高熵铌酸盐和稀土铌酸盐的微观结构、热膨胀系数和热导率。结果表明:高熵铌酸盐为单相单斜结构,掺杂的稀土元素分布均匀,存在明显的铁弹性域,铁弹性相变导致的体积膨胀基本可以忽略不计。相对于YNbO4的热膨胀系数(10.60×10^(-6)K^(-1),829℃)和热导率(3.12 W·m^(-1)·K^(-1),100℃),高熵(La_(0.2)Ho_(0.2)Er_(0.2)Y_(0.2)Yb_(0.2))NbO4陶瓷具有更高的热膨胀系数(11.19×10^(-6)K^(-1),686℃)和更低的热导率(2.34 W·m^(-1)·K^(-1),100℃),是潜在的新型热障涂层候选材料。
High-entropy(La_(0.2)Ho_(0.2)Er_(0.2)Y_(0.2)Yb_(0.2))NbO_(4) ceramics were successfully prepared by the solid-state reaction method.The microstructure,thermal expansion coefficient,and thermal conductivity of high entropy niobate and rare earth niobates were characterized.The results show that the high-entropy niobate has a singlephase monoclinic structure with obvious ferroelastic domains,the doped rare earth elements are uniformly distributed,and the volume expansion caused by the ferroelastic phase transformation can be ignored.Compared with the thermal expansion coefficient(10.60×10^(-6)K-1,829℃)and thermal conductivity(3.12 W·m^(-1)·K^(-1),100℃)of YNbO_(4),high entropy ceramic(La_(0.2)Ho_(0.2)Er_(0.2)Y_(0.2)Yb_(0.2))NbO_(4) has higher thermal expansion coefficient(11.19×10^(-6)K^(-1),686℃)and lower thermal conductivity(2.34 W·m^(-1)·K^(-1),100℃),which is a potential novel candidate material for thermal barrier coatings.
作者
张奕雄
王盼盼
何君杰
徐陆润
陶景超
赵晓峰
Zhang Yixiong;Wang Panpan;He Junjie;Xu Lurun;Tao Jingchao;Zhao Xiaofengg(Shanghai Key Laboratory of Materials Laser Processing and Modification,School of Materials Science and Engineering,Shanghai Jiaotong University,Shanghai 200240,China)
出处
《中国稀土学报》
EI
CAS
CSCD
北大核心
2024年第3期522-527,共6页
Journal of the Chinese Society of Rare Earths
基金
上海交通大学青年人才支持项目(AF0500148)资助。
关键词
热障涂层
高熵铌酸盐
热膨胀系数
热导率
稀土
thermal barrier coating
high entropy niobate
thermal expansion coefficient
thermal conductivity
rare earths
