| About this Abstract |
| Meeting |
Additive Manufacturing Benchmarks 2022 (AM-Bench 2022)
|
| Symposium
|
Additive Manufacturing Benchmarks 2022 (AM-Bench 2022)
|
| Presentation Title |
Optimizing Roller-based Spreading of Fine, Cohesive Metal Powders via DEM Simulations |
| Author(s) |
Reimar Weissbach, Patrick M. Praegla, Ryan Penny, Christoph Meier, Wolfgang A. Wall, John Hart |
| On-Site Speaker (Planned) |
John Hart |
| Abstract Scope |
Use of fine powders in binder jetting (BJ) is desirable for improved sintering kinetics and high final part density. However, for smaller particles, cohesive forces dominate gravitational forces, leading to poor powder flowability and clumping, which results in non-uniformity and low packing fractions in the spread layer. This typically necessitates use of roller-based mechanisms that apply high shear to the powder. As such, a detailed understanding of the relationship between powder cohesion and the mechanics that enable controlled spreading using rollers is necessary to advance process capabilities. Via discrete element (DEM) simulations that consider cohesion and enable high-fidelity analysis of boundary conditions from the roller and build surface, we study how high layer packing density as well as low surface roughness can be achieved, using Ti64 powder as a model system. Our results suggest material and size-specific spreading conditions (e.g., roller rotation and translation speed) that optimize packing density. |
| Proceedings Inclusion? |
Undecided |