About this Abstract |
Meeting |
2020 TMS Annual Meeting & Exhibition
|
Symposium
|
Advanced Solid Phase Processing Symposium
|
Presentation Title |
Elucidating the Role of Flash Heating in Ultrasonic Consolidation of Powder and Foils |
Author(s) |
Zachary Cordero, Austin A Ward |
On-Site Speaker (Planned) |
Zachary Cordero |
Abstract Scope |
Ultrasonic consolidation of powders and foils is a promising approach for manufacturing bulk materials with non-equilibrium structures and exotic properties. In this processing route, a punch presses on the feedstock and oscillates at ultrasonic frequencies perpendicular to the loading axis. These ultrasonic vibrations shear the surface asperities and disrupt the oxide overlayer on the feedstock to achieve metallurgical bonding. The ultrasonic vibrations have been observed to decrease the flow stress of the feedstock, making it easier for the feedstock to bond under a low normal stress; however, the physical mechanism that drives this softening is still a matter of debate. Some researchers attribute softening to frictional heating while others argue for an acoustic softening effect where elastic waves increase the mobility of glissile dislocations. Here we resolve this controversy by combining heat transfer theory and plasticity models to show that flash heating drives junction growth in ultrasonic consolidation processes. |
Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |