The Effect of B₂O₃–Li₂CO₃ Addition on Sintering Behavior and Dielectric Properties of Ba _0.6Sr_0.4TiO₃ Ceramics

Abstract:

Barium strontium titanate (Ba_0.6Sr_0.4TiO₃: BST) powders were prepared by the oxalate co-precipitation method. The ceramics from thus obtained BST powders with B₂O₃-Li₂CO₃ addition were prepared by conventional oxide mixing method. The powders and the ceramics were observed and analyzed by SEM and X-ray diffraction. The effects of B₂O₃-Li₂CO₃ addition and powder properties on the sintering behavior and the dielectric properties of BST-based ceramics were investigated. SEM results revealed that the BST powders are micron-sized with cauliflower-shaped rough surface leading the specific surface area reaches 18.52m²/g. In dilatometric studies, the ceramics without B₂O₃-Li₂CO₃ addition didn’t produce the desired shrinkage and dense microstructure at relative low temperatures (<1000°C). However, the sintering temperature is decreased to 850°C by addition of small amount (≤3wt %) of B₂O₃ and Li₂CO₃. This was also verified in sintered microstructures. The XRD results showed that the main phase of the ceramics was BST without any other crystalline phases of remarkable extent. With increasing of B₂O₃-Li₂CO₃ content, the permittivity and the tunability of the ceramics were decreased.

• Periodical: Advanced Materials Research (Volumes 197-198)
• Pages: 333-338
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.197-198.333
• Online since: February 2011
• Authors: Ming Li Li, Qiong Yu, Kun Ming Qian, Song Ji, Pi Yi Du
• Keywords: Barium Strontium Titanate, Dielectric Property, Microstructure, Sintering Aids

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