Microwave dielectric properties of (Ba1−xSrx)(Mg0.5W0.5)O3 ceramics. Issue 7 (August 2015)

• Record Type: Journal Article
• Authors: Lin, Yung-Jen; Wang, Sea-Fue; Chen, Ssu-Hao; Liao, Yi-Le; Tsai, Cheng-Long
• Is Part Of: Ceramics international. Volume 41:Issue 7(2015)
• Page Start: 8931
• Page End: 8935
• Publication Date: 2015-08
• Subjects: D. Perovskite -- Microwave dielectric properties -- Microstructure -- Densification; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2015.03.166
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: The densification, microstructural evolution and microwave dielectric properties of (Ba1− x Sr x )(Mg0.5 W0.5 )O3 ceramics with x =0, 0.25, 0.5 and 0.75 are investigated in this study. The sintering temperature of the (Ba1− x Sr x )(Mg0.5 W0.5 )O3 is significantly reduced from 1575 °C to 1400 °C as the x value increases from 0 to 0.25 and 0.50; this result is accompanied by the formation of the (Ba1− y Sr y )WO4 phase and a small quantity of second phase surrounding the grains. The grain size of the (Ba1− x Sr x )(Mg0.5 W0.5 )O3 ceramics is increased by raising the Sr 2+ content, which significantly lowers the sintering temperature. The microstructure of the (Ba0.75 Sr0.25 )(Mg0.5 W0.5 )O3 ceramic displays the smallest average grain size of approximately 0.8 μm, with a narrow grain size distribution. Without long annealing time, very high Q × f values are obtained for the (Ba1− x Sr x )(Mg0.5 W0.5 )O3 ceramics sintered at 1400–1575 °C for a duration of only 2 h. The (Ba0.75 Sr0.25 )(Mg0.5 W0.5 )O3 ceramic sintered at 1400 °C results in the best microwave dielectric properties, including ε r of 20.6, Q × f of 152, 600 GHz and τ f of +24.0 ppm/°C.