|About this Abstract
||Materials Science & Technology 2012
||Novel Sintering Processes and News in Conventional Sintering and Grain Growth
||Multiscale Thermal Processes in High Voltage Consolidation of Powders
||Evgeny Grigoryev, Eugene Olevsky
|On-Site Speaker (Planned)
Compressed metal powders have a very large electrical resistance due to the oxide layers on grains. A transition from an insulating to a conducting state of powder sample is observed as the applied current is increased. Experiments show that this transition comes from an electro-thermal coupling in the vicinity of the microcontacts between particles where microwelding and electric microexplosion occurs. This paper presents multiscale simulation results of the thermal processes occurring under electric pulse sintering of powder materials. The thermal processes in the contact zones of powder particles are characterized by significant spatial inhomogeneity and time dependence during this sintering. Their analysis and finding of the main regularities in the behavior of the powder material in the contact zones makes it possible to establish the optimal pulse electrical current parameters. The simulation results demonstrate the correlation between the modeling and experimental data for compacted powders of heat-resistant alloy.