| About this Abstract |
| Meeting |
2022 TMS Annual Meeting & Exhibition
|
| Symposium
|
Additive Manufacturing Fatigue and Fracture: Developing Predictive Capabilities
|
| Presentation Title |
Fatigue Crack Initiation Behavior of Laser Beam Powder Bed Fused IN718 |
| Author(s) |
Mohammad S. Dodaran, Muztahid Muhammad, Shuai Shao, Nima Shamsaei |
| On-Site Speaker (Planned) |
Shuai Shao |
| Abstract Scope |
The fatigue performance of certain additively manufactured alloys, such as IN718, is known to be less sensitive to the presence of defects. Fatigue failure in IN718 specimens is seen to be caused by cracks initiated from both persistent slip bands (PSB) and volumetric defects. This work is interested in laser beam powder bed fused (LB-PBF) IN718 and sheds light on the competition between the PSB driven and defect driven fatigue crack initiation using crystal plasticity (CP) simulations validated by experiments. It was found that shear localization, a precursor for fatigue crack initiation, is governed by local cyclic strain softening and is sensitive to both micro- and defect-structures. Longer crystallographic slip distances and larger defects can both promote the localization. The LB-PBF induced, large columnar grains can have diameters beyond hundreds of microns and are favorable for PSB governed fatigue crack initiation. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Additive Manufacturing, Copper / Nickel / Cobalt, Modeling and Simulation |