Effect of the Ba/Ti Ratio on the Microstructures and Dielectric Properties of Barium Titanate-Based Glass–Ceramics
Abstract:A series of BaTiO3 (BT)-based ferroelectric glass–ceramics have been prepared via controlled crystallization by varying the Ba/Ti ratio in an aluminum silicate glass composition, and the subsequent microstructure, phase evolution, and dielectric properties have been investigated. X-ray diffraction indicated that an increasing Ba/Ti ratio promoted the crystallization of BaTiO3 and BaAl2Si2O8 from the glass matrix, and the cracking of glass–ceramics appears to be correlated to mismatch in the thermal expansion coefficient among BaTiO3, BaAl2Si2O8, and the glass matrix. In addition, it was found that increasing the Ba/Ti ratio facilitated the formation of a dendrite structure with obvious porosity. The change in the Ba/Ti ratio in the glass notably modified the dielectric properties: a high Ba/Ti ratio in the glass resulted in an increased dielectric constant and decreased breakdown strength.
Document Type: Research Article
Affiliations: 1: Beijing Fine Ceramics Laboratory, State Key Laboratory of New Ceramics and Fine Processing, Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084, China 2: State Key Laboratory of New Ceramics and Fine Processing, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084, China
Publication date: 2009-06-01