Fabrication and influence of sintering temperature on material properties of Mn/Y codoped Ba_(0.67)Sr_(0.33)TiO_3 ceramics via using citrate-nitrate combustion derived powder

摘要

Mn/Y codoped Ba_(0.67)Sr_(0.33)TiO_3 (BST) ceramics were fabricated via using citrate-nitrate combustion derived powder, and the effect of sintering temperature on microstructure and electrical properties of BST ceramics were mainly investigated. Agglomerated BST powder, with nano-size particles, was obtained at 700 °C. Sintering temperature has a strong influence on the microstructure and electrical properties of BST ceramics. The density, dielectric and ferroelectric properties are improved by optimizing sintering temperature. The relative density of the BST ceramics sintered at an optimum sintering temperature (1260 °C) reaches 97.9% of the theoretical value. The measured values of remanent polarization (2Pr) and coercive field (2?c) of the BST ceramics are 16.33 μC/cm~2 and 3.548 kV/cm, respectively. The dielectric loss of the BST ceramics is 0.003 in the para-electric state. Therefore, nanocrystalline powder, sintering with optimum temperature and Mn/Y codoping help improve the electrical properties of BST ceramics.