Influence of the Multi Step Flash Sintering technique on the microstructural control of ZrO2

• Grant number: 19/14677-9
• Support Opportunities: Regular Research Grants
• Duration: June 01, 2020 - January 31, 2023
• Field of knowledge: Engineering - Materials and Metallurgical Engineering - Nonmetallic Materials
• Principal Investigator: Eliria Maria de Jesus Agnolon Pallone
• Grantee: Eliria Maria de Jesus Agnolon Pallone
• Host Institution: Faculdade de Zootecnia e Engenharia de Alimentos (FZEA). Universidade de São Paulo (USP). Pirassununga , SP, Brazil
• Associated researchers: Julieta Adriana Ferreira ; Rafael Vieira de Sousa

Abstract

The sintering flash technique (SF), presented in the literature in the last decade, consists of the electric field application in the sample concomitant with increasing the temperature of the furnace during the sintering. Materials with negative temperature coefficient have their electrical resistance inversely proportional to the temperature. Thus, at a given temperature, a significant electric current is induced through the sample. This electric current heats the sample abruptly, causing its retraction/densification in a few seconds. The relationship between the parameters (such as electric current density, the intensity of the electric field, electrical current mode, and others) used in the SF and the physical and microstructural properties obtained is not established. The understanding of the mechanisms involved in the process is still in debate, which so far makes it difficult to define the best conditions to be used. The heterogeneity of the microstructure is a factor that has been discussed. In this sense, the objective of this project is to develop a methodology to control the microstructure of 3Y-TZP and 8Y-TZP using the technique Multi Flash Step Sintering (MSFS). For this, the impedance technique interleaved with the MSFS and the experimental analysis by combinations of multiple variables (furnace temperature, electric field strength, pressure, electric current density, among others) in the different materials studied will be used, aiming to obtain sample information throughout the sintering process. With the results obtained, we intend to get models based on linear regression and artificial neural networks (RNA), aiming the prediction of characteristics of the sintered samples in the different conditions of the MSFS technique. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

STORION, ANA G.; LAVAGNINI, ISABELA R.; CAMPOS, V, JOAO; DA SILVA, JOAO G. P.; MAESTRELLI, SYLMA C.; PALLONE, ELIRIA M. J. A.. Effect of thermal insulation on microstructural homogeneity and onset temperature of flash sintered materials. Journal of the European Ceramic Society, v. 41, n. 15, p. 7807-7815, DEC 2021. (18/11143-0, 19/14677-9, 18/04331-5)

V. CAMPOS, JOAO; LAVAGNINI, ISABELA R.; AVILA, VIVIANA; YOON, BOLA; GHOSE, SANJIT; RAJ, RISHI; PALLONE, ELIRIA M. J. A.; JESUS, LILIAN M.. On the Arrhenius-like behavior of conductivity during flash sintering of 3 mol% yttria stabilized zirconia ceramics. SCRIPTA MATERIALIA, v. 203, OCT 2021. (18/04331-5, 19/03786-1, 19/14677-9)