Dielectric and pyroelectric properties of barium strontium calcium titanate ceramics

(Ba0.6Sr0.3Ca0.1)TiO3 powders were prepared by the sol-gel method using a solution of Ba, Sr and Ca acetate and Ti isopropoxide, and the specimens doped with MnCO3 (0.1 Mol%) and Y2O3 (0.5 mol%) were fabricated by the cold isostatic press method. The urethane pot and zirconia ball were used in the mixing and grinding process, and the green pellets were sintered at 1450 degreesC for 2 h in the alumina crucible. The specimen exhibited a dense and void-free grain structure with grain size of about 3 Pm. The dielectric constant and the dielectric loss at Curie temperature were 16,600 and 1.2%, respectively. The specimen under a 4 kV cm(-1) DC bias field showed the maximum pyroelectric coefficient of 550 x 10(-9) C cm(-2) K-1 at Curie temperature. The figure of merit F.M.D* for specific detectivity (D*) of the specimen, applied with DC 8 kV cm(-1) bias field, was the highest value of 17.6 x 10(-9) C cm J(-1) at Curie temperature. (C) 2002 Elsevier Science Ltd. All rights reserved.