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.