Correlation between structure and microwave dielectric properties of low-temperature-fired Mg2SiO4 ceramics

Journal Article · Thu Mar 15 04:00:00 EDT 2018 · Materials Research Bulletin

DOI:https://doi.org/10.1016/J.MATERRESBULL.2017.11.036· OSTI ID:22805466

Lai, Yuanming; Tang, Xiaoli; Zhang, Huaiwu ^[1]; Liang, Xiaofeng ^[2]; Huang, Xin; Li, Yuanxun; Su, Hua ^[1]

---

1. State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054 (China)
2. Medical Institute Department, Sichuan College of Traditional Chinese Medicine, Mianyang 621000 (China)

Highlights: • Mg{sub 2}SiO{sub 4}–xLiF ceramics could be sintered at 900 °C. • The microwave dielectric properties were significantly dependent on the structure. • The following optimum properties were achieved in the x = 8 wt% ceramics. • Temperature stability of Mg{sub 2}SiO{sub 4}–8 wt% LiF–6.0vol% CaTiO{sub 3} ceramics was obtained. • These ceramics also exhibited excellent chemical compatibility with Ag. - Abstract: Mg{sub 2}SiO{sub 4}–LiF ceramics were fabricated via a conventional solid-state process and sintered at 900 °C. The secondary phase, Li{sub 2}SiO{sub 3}, was observed with ≤6 wt% LiF, and the Li{sub 2}MgSiO{sub 4} phase was detected with ≥8 wt% LiF. The relative density and secondary phase can account for the decrease in the ε{sub r} with an increase in LiF. The degree of crystallization, unit cell volume, secondary phase, and microstructure correlated with the Q × f values. The value of the τ{sub f} was related to the distortions in the Mg(1)O{sub 6} octahedron and the secondary phase. The sample exhibited excellent properties for Mg{sub 2}SiO{sub 4}–8 wt% LiF with ε{sub r} = 6.1, Q × f = 109719 GHz, and τ{sub f} = − 61 ppm/°C. The temperature stability of the Mg{sub 2}SiO{sub 4}–8 wt%LiF–6 vol%CaTiO{sub 3} ceramics was obtained with ε{sub r} = 7.1, Q × f = 31091 GHz and τ{sub f} = − 2.0 ppm/°C. Mg{sub 2}SiO{sub 4}–LiF–CaTiO{sub 3} ceramics provide excellent chemical compatibility with Ag.

• OSTI ID: 22805466
• Journal Information: Materials Research Bulletin, Journal Name: Materials Research Bulletin Vol. 99; ISSN MRBUAC; ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CERAMICS
CRYSTALLIZATION
DIELECTRIC PROPERTIES
GHZ RANGE
LITHIUM FLUORIDES
LITHIUM SILICATES
MAGNESIUM SILICATES
MICROSTRUCTURE
MICROWAVE RADIATION
SOLIDS
STABILITY
TEMPERATURE RANGE 0065-0273 K