Low-temperature sintering and electrical properties of chemically w-doped Bi 4Ti 3O 12 ceramics

Abstract

High temperature piezoelectric ceramics based on W 6+-doped Bi 4Ti 3O 12(W-BIT) have been prepared by a chemical route based on hydroxides coprecipitation. The low calcination temperature (650°C for 1 h) gave rise to a BIT powder consisting of small reactive particles. The characteristics of the calcined powder along with the narrow pore size distribution in the green compacts allowed a rapid densification, >99% ρ th at a very low temperature (900°C for 2 h). The microstructure study revealed a plate-like morphology with small platelets that did not grow significantly until high temperature (1100°C). The chemically prepared W 6+-doped BIT materials showed an electrical conductivity value 2–3 orders of magnitude lower than undoped samples. The decrease in the electrical conductivity allowed the W-doped samples to be poled and preliminary piezoelectric results were obtained.