Flash sintering for BaTiO₃ with square alternating current field including zero-field duration

Abstract

The shrinkage behavior of barium titanate (BaTiO₃) green compacts during flash sintering with a square alternating current (AC) field including a zero-field duration (AC-pulse wave) was investigated. It was found that an AC-pulse wave is effective for the densification of BaTiO₃ green compacts without reduction and discharge, which is confirmed by transmission electron microscopy and electron energy loss spectroscopy. BaTiO₃ sintered polycrystal was obtained at a furnace temperature of 1000 °C by the optimal AC-pulse conditions of 285 V/cm at 250 Hz and a duty ratio of 30 %. A waveform with alternating polarity and the inclusion of a zero-field duration is shown to be possibly useful for flash sintering of oxide materials including altervalent cations.