放电等离子烧结
材料科学
陶瓷
等离子体
烧结
SPARK(编程语言)
相(物质)
单相
矿物学
复合材料
计算机科学
核物理学
程序设计语言
工程类
化学
有机化学
物理
电气工程
作者
Lucile Féger,Fabien Giovannelli,Gaurav Vats,J. Maia Alves,B. Pignon,Ekhard K. H. Salje,I. Monot-Laffez,Guillaume F. Nataf
标识
DOI:10.1016/j.jeurceramsoc.2023.07.060
摘要
Potassium tantalate (KTaO$_{3}$) is a promising material for dielectric applications at low temperature. However, dense and single-phase ceramics cannot be obtained by conventional sintering because of the evaporation of potassium that leads to secondary phases. Here, we demonstrate that spark plasma sintering is a suitable method to obtain dense and single-phase KTaO$_{3}$ ceramics, by optimizing three parameters: initial composition, temperature, and pressure. A 2 mol% K-excess in the precursors leads to a large grain growth and dense single-phase ceramics. Without K-excess, a small amount of secondary phase (K$_{6}$Ta$_{10.8}$O$_{30}$) is observed at the surface but can be removed by polishing. At 10 K, the dielectric permittivity is 4 times higher in the ceramic from the 2 mol% K-excess powder, because of the larger grain size. The thermal conductivity decreases with decreasing grain size and stays above the thermal conductivity of KNbO$_{3}$ ceramics.
科研通智能强力驱动
Strongly Powered by AbleSci AI