Influence of geometry on thermal gradients and hotspot formation during flash sintering

Abstract

Hotspot or preferential current path formation is a major problem halting the advance of flash sintering as an industry applicable densification method. In-situ infrared thermal imaging shows significant dependence of the surface temperature distribution on the sample geometry, causing significant changes in the onset parameters, the course of the flash event and sample quality. Current-ramped flash sintering is compared to conventional flash sintering experiments and reveals an effective reduction in temperature differences. The role of the setup design on the thermal losses and the gradients is highlighted.