Effect of thermal insulation on microstructural homogeneity and onset temperature of flash sintered materials

Autor(es)

Storion, Ana G. ^[1] ; Lavagnini, Isabela R. ^[1] ; Campos, V, Joao ; da Silva, Joao G. P. ^[2] ; Maestrelli, Sylma C. ^[3] ; Pallone, Eliria M. J. A. ^{[4, 5]}

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Postgrad Programme Mat Sci & Engn, USP FZEA, Av Duque Caxias Norte 225, BR-13635900 Pirassununga - Brazil

^[2] Forschungszentrum Julich, Inst Energy & Climate Res IEK 1, D-52425 Julich - Germany

^[3] Univ Fed Alfenas, Jose Aurelio Vilela, 11999, Cidade Univ, BR 267, Km 5, BR-37715400 Pocos De Caldas, MG - Brazil

^[4] Univ Sao Paulo, Fac Anim Sci & Food Engn FZEA, Dept Biosyst Engn, BR-13635900 Pirassununga, SP - Brazil

^[5] Campos, Joao, V, Univ Sao Paulo, Postgrad Programme Mat Sci & Engn, USP FZEA, Av Duque Caxias Norte 225, BR-13635900 Pirassununga - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of the European Ceramic Society; v. 41, n. 15, p. 7807-7815, DEC 2021.
• Citações Web of Science: 0

Resumo

The present work aimed to reduce the microstructure heterogeneity inherent to flash sintering by using alumina blankets as a thermal insulator around ZnO cylindrical samples during the sintering process, under different electric field conditions. Thermal insulation significantly reduced the flash onset temperature and the grain size heterogeneity. For higher electric fields, a temperature reduction as high as 480 degrees C was observed, which also led to lower densification. These findings were discussed in terms of changes in the heat loss dynamics coupled with the adsorbed water retention, both promoted by the applied thermal insulation. A model to estimate the temperature at stage III of flash sintering was proposed. The final temperature reached with thermal insulation did not differ significantly from the ones without it. Thus, thermal insulation could represent an alternative route to flash sinter materials with lower furnace temperatures with energy savings up to 78 % and a more homogeneous microstructure. (AU)

• Processo FAPESP: 18/11143-0 - Influência dos parâmetros da sinterização flash na densificação e microestrutura do ZnO
• Beneficiário: Ana Gabriela Storion
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 19/14677-9 - Influência da técnica Multi Step Flash Sintering no controle microestrutural da ZrO2
• Beneficiário: Eliria Maria de Jesus Agnolon Pallone
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 18/04331-5 - Instrumentação e automação de forno tubular adaptado à técnica flash sintering
• Beneficiário: João Vitor Campos
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto