Phase Relations in Ba6−3xLn8+2xTi18O54 (Ln = Nd & Sm) Electroceramics. (18th September 2013)

• Record Type: Journal Article
• Authors: Snashall, Amanda L.; Liu, Yun; Brink, Frank; Withers, Ray L.; Cooper, Steven
• Other Names: Wang Danyang Academic Editor.
• Is Part Of: Advances in condensed matter physics. Volume 2013(2013)
• Publication Date: 2013-09-18
• Subjects: Condensed matter -- Periodicals; Condensed matter; Periodicals; 530.41
• DOI: 10.1155/2013/373079
• Languages: English
• ISSNs: 1687-8124

Abstract

Abstract : A careful, systematic investigation of Ba 6 − 3 x L n 8 + 2 x Ti 18 O 54 (BLnTss) ceramics has been performed in order to understand the relationship between composition, microstructure evolution, and microwave dielectric properties. In this paper, we report the effects of composition, morphology, and sintering time on the phase relations and properties of BLnTss (Ln = Nd, Nd/Sm, Sm) ceramics. The microwave dielectric properties of the materials are reported in addition to phase characterisation and structural analysis via X-ray diffraction and field emission scanning electron microscopy coupled with energy dispersive X-ray spectroscopy. BLnTss, x = 0.33, ceramics with high Sm content are found to experience a severe degradation of Qf and changes in τ cf trending, associated with the onset of globular and needle-like grain morphology and a Ba-Ti rich phase. x = 0.67 ceramics with high Nd content are found to exhibit a secondary phase (Nd2 Ti2 O7 ) upon prolonged sintering which resulted in beneficial changes to Qf and τ cf without affecting ε r . Two BLnTss ceramics compositions with near-zero τ cf were successfully synthesised with high Qf and ε r values.