About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
|
Additive Manufacturing of Metals: Applications of Solidification Fundamentals
|
Presentation Title |
Microstructure Evolution in an As-Built IN625 Thin-wall Fabricated Via Laser Powder Bed Fusion |
Author(s) |
Pardis Mohammadpour, Andre Phillion, Hui Yuan |
On-Site Speaker (Planned) |
Andre Phillion |
Abstract Scope |
The unique thermal and solidification conditions during manufacturing of Laser Powder Bed Fusion (LPBF) parts results in multiscale microstructure heterogeneity leading to a variability in mechanical properties of LPBF parts. This study focuses on the process-structure-properties relationship in an as-built multi-layer LPBF IN625 part. Numerical thermal simulation, modern electron microscopy techniques, nanohardness test, and DIffusion-Controlled TRAnsformations (DICTRA) methods were utilized to investigate the spatial heterogeneity in terms of grain size and morphology, Primary Dendrite Arm Spacing (PDAS), microsegregation pattern, precipitation, and hardness along the build. It was found that the as-built microstructure contains mostly columnar Nickel–Chromium (γ) dendrites growing epitaxially along the build direction. Moreover, smaller grains, melt pools, and PDAS, and higher cooling rate and hardness were observed in the bottom layers in comparison to those in the top layers. Microsegregation patterns in multiple layers were also simulated using DICTRA and were compared with the microscopy results. |
Proceedings Inclusion? |
Planned: |
Keywords |
Additive Manufacturing, Solidification, Characterization |