Spark plasma sintering of hydrothermally synthesized bismuth ferrite

Abstract

Bismuth ferrite, BiFeO3 (BFO), powder was synthesized by hydrothermal method from Bi(NO3)(3)center dot 5H(2)O and Fe(NO3)(3)center dot 9H(2)O as precursors. The synthesized powder was further sintered using spark plasma sintering (SPS). The sintering conditions were optimized in order to achieve high density, minimal amount of secondary phases and improved ferroelectric andmagnetic properties. The optimal structure and properties were achieved after spark plasma sintering at 630 degrees C for 20min, under uniaxial pressure of 90MPa. The composition, microstructure, ferroelectric and magnetic properties of the SPS samples were characterized and compared to those of conventionally sintered ceramics obtained from the same powder. Although the samples sintered using conventional method showed slightly lower amount of secondary phases, the spark plasma sintered samples exhibited favourable microstructure and better ferroelectric properties.