Effects of CuO Addition on the Microstructure and Microwave Dielectric Properties of MgTa₂O₆ Ceramics

Abstract:

MgTa₂O₆ powders with the tetragonal phase have been synthesized by mixed oxide method at 1100 °C when the molar ratios of MgO and Ta₂O₅ increase from 1:1 to 1.2:1. The microwave dielectric properties of sintered MgTa₂O₆ ceramics without additives at 1400°C for 6h, which consists of tetragonal and orthorhombic phases have been investigated. The results show that the ceramic possesses a dielectric constant of 27.5, a high Q×f value of 156000 GHz and a temperature coefficient of resonant frequency of 21.6 ppm/°C at 6-10 GHz. Different amounts of CuO has been used as sintering additives to lower the sintering temperature of MgTa₂O₆ ceramics. The effect of the CuO doping agent on the microstructure, densification and the microwave dielectric properties of MgTa₂O₆ ceramics has been studied using X-ray diffraction, scanning electron microscope and HP8720ES network analyzer. The results indicate that the 1-5 wt. % CuO dopant can lower the sintering temperatures of this materials dramatically. The second phase of CuTa₂O₆ was found in MgTa₂O₆ ceramics, which caused the deterioration of Q×f value of the ceramics.

• Periodical: Key Engineering Materials (Volumes 512-515)
• Pages: 1222-1225
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.512-515.1222
• Online since: June 2012
• Authors: Bao Jian Fu, Ying Chun Zhang, Xiao Li Su, Yan Hong Liu, Ming Hong
• Keywords: Low Temperature Sintering, MgTa₂O₆, Microwave Dielectric Ceramics

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