Preparation and Electrical Properties of Sr₂KNb₅O₁₅ Ceramics by Molten Salt Method

Abstract:

Sr₂KNb₅O₁₅ ceramic powders have been synthesized by molten salt method, ceramics were sintered via a pressureless sintering method. The effect of calcining temperature on the phase composition and microstructure of ceramic powders were investigated by XRD and SEM analysis. The results show that microstructure of ceramic powders changed from acicular to platy, and the average size of ceramic powders become bigger with the calcining temperature increased. The optimal calcining temperature was 1200°C, and the length and diameter of ceramic powders was about 1-5 mm and 0.2-1 mm, thus the aspect ratio of ceramic powders was about 1-5. The influence of sintering temperature on density, microstructure and electrical properties of the ceramics were systematically analyzed. The results indicate that density and electrical properties of the ceramics first increased then decreased with increasing the sintering temperature. When the sintering temperature was 1400°C, the ceramics show optimized relative density and electrical properties (d₃₃=40 pC/N, e_r=616, tand=0.029, E_c=9.83 kV/cm, P_r=32.50 mC/cm²).

• Periodical: Key Engineering Materials (Volume 591)
• Pages: 194-199
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.591.194
• Online since: November 2013
• Authors: Tian Hang Zhang, Yan Gai Liu, Cheng Xue Yang, Jin Qiu Zhao, Zhao Hui Huang, Ming Hao Fang
• Keywords: Microstructure, Molten Salt Method, Sr₂KNb₅O₁₅, Tungsten Bronze Structure

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