Electric current activated sintering (ECAS) of undoped and titanium-doped BiFeO3 bulk ceramics with homogeneous microstructure. Issue 6 (June 2019)

• Record Type: Journal Article
• Authors: Bernardo, Mara S.; Jardiel, Teresa; Caballero, Amador C.; Bram, Martin; Gonzalez-Julian, Jesus; Peiteado, Marco
• Is Part Of: Journal of the European Ceramic Society. Volume 39:Issue 6(2019)
• Page Start: 2042
• Page End: 2049
• Publication Date: 2019-06
• Subjects: ECAS sintering -- Flash and FAST sintering -- BiFeO3 -- Homogeneous microstructure -- DC and AC electric field; Ceramic materials -- Periodicals; Composite materials -- Periodicals; Matériaux céramiques -- Périodiques; Composites -- Périodiques; Ceramic materials; Composite materials; Periodicals; Electronic journals; 666.05
• DOI: 10.1016/j.jeurceramsoc.2019.01.045
• Languages: English
• ISSNs: 0955-2219

Abstract

Abstract: BiFeO3 ceramics have been consolidated applying an electric current activated/assisted sintering (ECAS) methodology under different electrical conditions. DC experiments produce a flash sintering regime by which the bulk cylindrical specimens densify in a few seconds; however, this goes together with a strong localization of the current flow within the material, leading to a dramatic lack of microstructural and compositional homogeneity. The situation changes under the alternate field; a more gradual FAST (Field Assisted Sintering) event is produced which allows the attainment of an exceptional microstructural homogeneity through the whole sintered compacts. Upon Ti-doping the overall diffusivity of the system is delayed but the AC conditions again yield a remarkable microstructural homogeneity in the consolidated material, this time even at the nanoscale level. Accordingly, bulk BiFeO3 ceramics with homogeneous micro-nanostructure can be successfully prepared by an ECAS methodology and at lower temperatures and much shorter times than by conventional solid-state sintering.