Development of an instrumented and automated flash sintering setup for enhanced process monitoring and parameter control

• Published in: Journal of the European Ceramic Society Vol. 39; no. 2-3; pp. 531 - 538
• Main Authors: Campos, João Vitor, Lavagnini, Isabela Reis, Sousa, Rafael Vieira de, Ferreira, Julieta Adriana, Pallone, Eliria Maria de Jesus Agnolon
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.02.2019
• Subjects: 3YSZ; Field-assisted sintering technique; Multi step flash sintering; Zirconia; Zirconia; Field-assisted sintering technique; 3YSZ; Multi step flash sintering
• ISSN: 0955-2219; 1873-619X
• DOI: 10.1016/j.jeurceramsoc.2018.09.002

Heterogeneous grain size distributions due to cathodic reduction of samples sintered by flash sintering (FS) are a recurring problem. Herein, we present an experimental setup for FS with refined control of the process parameters, especially the electric current density, to control the power peak that could reduce the grain size heterogeneity of sintered materials. The real-time control of the equipment enabled the development of a Multi-Step Flash Sintering (MSFS) process. This technique involves varying the maximum current density at the onset of the abrupt shrinkage of the sample during the flash phenomenon, smoothing the shrinkage and power density curves, avoiding power peak and allowing its control in real time. Tetragonal stabilised zirconia (3YSZ) was sintered in this equipment by both FS and MSFS. Preliminary results of this study were promising in terms of density control and improvement of grain size homogeneity.