Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
Prediction of the Stability Map of a Non-Conventional Sintering Process by Using a Dynamic Bifurcation Model
Submission Author:
João Gustavo Pereira da Silva , SP
Co-Authors:
João Gustavo Pereira da Silva, Sidney Bruce Shiki, Hazim Ali Al-Qureshi
Presenter: João Gustavo Pereira da Silva
doi://10.26678/ABCM.COBEM2023.COB2023-1155
Abstract
Flash sintering is an innovative sintering method in which a critical combination of electrical field and temperature triggers a sudden densification within seconds. The conditions for flash sintering should be of a controlled thermal runaway in the voltage control mode that should be changed to current control in order to avoid current localization. Nonlinear dynamics can be used to describe this method by the means of a thermal runaway model explaining the evolution of variables during flash sintering. A theoretical processing map for successful flash sintering can be created by using two different transition lines: An explicit solution for the folding points in the voltage control mode temperature equilibrium surface and a criterion for the formation of hotspots based on perturbation methods. The results of this analysis show that the hotspot formation is inherent to the voltage control mode as a function of materials properties, process variables and sample geometry. The stability of the voltage and current control modes is examined by the use of bifurcation theory and can explain the assymptotic behavior in the current control mode in conventional flash sintering and the whole process evolution the method of current ramp controlled flash sintering.
Keywords
