Effect of excess PbO on phase formation and properties of (Pb 0.90Ba0.10)ZrO3 ceramics

• Main Authors: Bongkarn T., Rujijanagul G., Milne S.J.
• Format: Article
• Language: English
• Published: 2014
• Online Access: http://www.scopus.com/inward/record.url?eid=2-s2.0-14644444586&partnerID=40&md5=88e53c612f8f3c251e64a0aa98c168ef; http://cmuir.cmu.ac.th/handle/6653943832/4997
• Institution: Chiang Mai University

Polycrystalline samples of (Pb0.90Ba0.10)ZrO 3 (PBZ) were prepared by a mixed oxide, solid-state reaction method. Excess PbO (3, 5 or 10 wt.%) was introduced prior to powder calcination to compensate for any PbO that may have been lost from the samples due to volatilisation during heat treatments. X-ray diffraction revealed that, compared to samples made from stoichiometric starting mixtures, a starting excess of PbO of ≥ wt.% increased the proportion of the rhombohedral PBZ phase which coexisted with the antiferroelectric orthorhombic phase. Microstructurally, excess PbO produced an increase in average grain size, from ∼1 μm for no excess to ~1.5 μm for ≥3 wt.% excess PbO. The fractured surfaces indicated predominantly intra-granular fracture in samples with no added PbO, or 3 wt.% excess PbO, whereas the 5 and 10 wt.% excess PbO samples displayed mainly inter-granular fracture. Dielectric constant-temperature plots showed a maximum peak value of 12,700 for the 3 wt.% sample which was also the most dense sample. © 2005 Elsevier B.V. All rights reserved.