Abstract
A key challenge in additive manufacturing (AM) of aluminum-based parts has been the formation of cracks and porosity during the processes. Multicomponent powder beds containing high-melting temperature, highly reactive elements (e.g., Zr and Sc) show promise for improving processibility and reducing crack and pore formation in such alloys. Melting and mixing of these elements in the base alloy during the AM process is yet to be fully understood. This paper describes a multiphysics modeling approach for investigating melt pool dynamics, keyhole and pore formation, and mixing phenomena in multicomponent powder beds. The discrete element method (DEM) is used to generate powder beds with randomly distributed particles of varying sizes. A thermal multi-phase flow model is coupled with a laser welding model in this approach, which includes multiple thermophysical phenomena and laser-material interactions. The multiphysics model was validated using available experimental results in the literature. Through this approach, not only the melt pool dynamics and keyhole morphology, but also the pore formation and mixing evolution during the AM processes, can be quantified for a wide range of process parameters (e.g., laser power and scan speed). To demonstrate the efficacy and application of this method, we thoroughly investigated the additive manufacturing of an Al – Zr powder bed system. The results reveal that the mixing of the alloying element, Zr, is heavily influenced by flow patterns in the melt region and keyhole formation.
| Original language | English (US) |
|---|---|
| Article number | 103481 |
| Journal | Additive Manufacturing |
| Volume | 67 |
| DOIs | |
| State | Published - Apr 5 2023 |
Funding
This research received funding from the DEVCOM Army Research Laboratory under Cooperative Agreement Numbers W911NF-20-2-0292 and W911NF-21-2-0199. The views and conclusions contained in this document are those of the authors and should not be interpreted as representing official policies, either expressed or implied, of the Army Research Laboratory or the US Government. The US Government is authorized to reproduce and distribute reprints for Government purposes notwithstanding any copyright notation herein. Discussions with Prof. David Dunand at Northwestern University on multicomponent alloying in AM are gratefully acknowledged. We are grateful for the reviewers' constructively critical comments and time spent on our paper, which significantly improved it. We would like to thank Drs. Ibai Mugica, Marcin Serdeczny, and Mr. Sarang Deshpande of FLOW-3D for their professional support and time. This research received funding from the DEVCOM Army Research Laboratory under Cooperative Agreement Numbers W911NF-20-2-0292 and W911NF-21-2-0199 . The views and conclusions contained in this document are those of the authors and should not be interpreted as representing official policies, either expressed or implied, of the Army Research Laboratory or the US Government. The US Government is authorized to reproduce and distribute reprints for Government purposes notwithstanding any copyright notation herein. Discussions with Prof. David Dunand at Northwestern University on multicomponent alloying in AM are gratefully acknowledged. We are grateful for the reviewers' constructively critical comments and time spent on our paper, which significantly improved it. We would like to thank Drs. Ibai Mugica, Marcin Serdeczny, and Mr. Sarang Deshpande of FLOW-3D for their professional support and time.
Keywords
- Aluminum alloys
- Binary powder beds
- Discrete element method
- Finite element method
- Metal additive manufacturing
- Mixing evolution
- Multi-material
- Multiphysics
- Phase transformation
- Solidification
- Thermal-fluid model
- Zirconium
ASJC Scopus subject areas
- Biomedical Engineering
- General Materials Science
- Engineering (miscellaneous)
- Industrial and Manufacturing Engineering
