Engineering Commons^™

Electric Field Effects On Grain Boundary Formation And Grain Growth, Klaus Van Benthem, Hasti Majidi, Jorgen Rufner, Wei Qin

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

The application of electric fields can enable the accelerated consolidation of materials during field assisted sintering, such as spark plasma sintering or flash sintering. Although such techniques are already employed for the synthesis of a wide variety of microstructures with unique macroscopic properties, a fundamental understanding of the atomic-scale mechanisms for grain boundary formation and subsequent migration in the presence of electrostatic potentials is mostly absent from the literature. We have designed experiments to specifically de-couple the effects of heating and applied electrostatic fields during consolidation. In situ transmission electron microscopy studies were carried out with new sample holder designs …

Microscopic Densification Mechanisms Of Metallic Systems By Spark Plasma Sintering, Jean Philippe Monchoux

Electric Field Assisted Sintering and Related Phenomena Far From Equilibrium

This study reports on the microscopic mechanisms accounting for the fast densification kinetics of metallic materials processed by spark plasma sintering (SPS). Metallic systems have been chosen in reason of their elevated electric conductivity. Hence, an important fraction of the electric current of the SPS passes through the powder, and electrically induced new mechanisms, or acceleration of conventional ones (e.g. plasticity, diffusion), can be expected. TiAl powder and Ag-Zn diffusion couple have thus been chosen to study the influence of the electric current on plasticity and on diffusion, respectively.

An originality of this work was to observe by transmission electron …