Structural evolution, sintering behavior and microwave dielectric properties of (1−x)Li{sub 2}TiO{sub 3} + xLiF ceramics
Graphical abstract: - Highlights: • Structure, sinterability and dielectric properties of LiF-doped Li{sub 2}TiO{sub 3} were studied. • Li{sub 2}TiO{sub 3} can be densitied (TD 98%) at lower sintering temperature by LiF additions. • Excellent microwave dielectric properties could be obtained. - Abstract: Structural evolution, sintering behavior, and microwave dielectric properties of (1−x)Li{sub 2}TiO{sub 3} + xLiF (0.05 ≤ x ≤ 0.70) ceramics have been studied by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Raman spectra, thermal dilatometry and microwave resonant measurement at the frequency of about 7–11 GHz. The results show that Li{sub 2}TiO{sub 3} can form limited solid solution with LiF (x ≤ 0.4) and LiF second phase appeared when x{sup 3}0.5. The structure of the solid solution transformed from ordered monoclinic phase (β-Li{sub 2}TiO{sub 3} (ss)) to disordered cubic rock salt (α-Li{sub 2}TiO{sub 3} (ss)) when x{sup 3}0.15. The presence of short range ordering was confirmed for the cubic phase. The sinterability was considerably improved by doping with LiF. Densified ceramics with about 95–98% theoretical density could be obtained for the doped compositions after sintering at 900–1150 °C/2 h. An optimized microwave dielectric properties with ε{sub r} of ∼23.6, Q × f of ∼108,000 GHz and τ{sub f} of ∼4.2 ppm/°C could be obtained for the x = 0.1 composition after sintering at 1100 °C/2 h.
- OSTI ID:
- 22341715
- Journal Information:
- Materials Research Bulletin, Vol. 48, Issue 8; Other Information: Copyright (c) 2013 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0025-5408
- Country of Publication:
- United States
- Language:
- English
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