Influence of forming methods on the microstructure of 3YSZ flash-sintered ceramics

Author(s)

Lavagnini, Isabela R. ; Campos, Joao, V ; Jesus, Lilian M. ; Pallone, Eliria M. J. A.

• Document type: Journal article
• Source: MATERIALIA; v. 22, p. 6-pg., 2022-04-19.

Abstract

We evaluated the influence of three different forming methods (uniaxial and isostatic pressings and slip casting) on the densification and microstructure of cylindrical flash sintered 3mol% yttria-stabilized zirconia (3YSZ) ceramics. Conventional sintering was also analyzed as a comparison. Irrespective of the forming method applied, all the conventionally and the flash sintered specimens presented high final densities. Regarding the grain size distribution, while conventionally sintered specimens presented homogeneity over the entire ceramics, flash sintering yielded specimens with grain size heterogeneity depending on the forming method used. The microstructure of the specimens prepared with slip casting was homogeneous. On the other hand, uniaxial pressure induced bigger grains at the core of the ceramics. This heterogeneity is attributed to the presence of green density gradients in the samples prepared by uniaxial pressing, which affects the current flow and, consequently, the heat distribution within the specimens. (AU)

• FAPESP's process: 18/19370-6 - Electric-Field Assisted Processing of Electroceramics: (micro)structural characteristics and dielectric properties
• Grantee: Lilian Menezes de Jesus
• Support Opportunities: Scholarships abroad - Research
• FAPESP's process: 18/04331-5 - Instrumentation and automation of a furnace adapted to flash sintering
• Grantee: João Vitor Campos
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• FAPESP's process: 21/06509-9 - Ionic conductor glass-ceramics sintering with concurrent crystallisation using flash sintering
• Grantee: João Vitor Campos
• Support Opportunities: Scholarships in Brazil - Post-Doctoral