Direct Observation of Processes at Particle-to-Particle Contacts during Electric Pulse Consolidation of a Titanium Powder

Abstract

Direct high-speed micro video recording data proved the existence of highly overheated zones at contacts of powder particles through which electric current pulses about 1 ms long were sent. The overheating might exceed 1600 K and could give rise to liquid-phase sintering necks, the sizes of which correlated well with the sizes of the overheated zones. Temperature field microheterogeneities during electric pulse heating of the powder medium gave an insight into unusually high rates of consolidation of powder materials during spark plasma sintering.