About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Additive Manufacturing Fatigue and Fracture
|
| Presentation Title |
Factors Affecting Fatigue- and Toughness-based Processing Windows for LPBF Ti-6Al-4V |
| Author(s) |
John J. Lewandowski, Austin Ngo, Brett Ley |
| On-Site Speaker (Planned) |
John J. Lewandowski |
| Abstract Scope |
The effects of systematic changes in P-V conditions for LPBF Ti-6Al-4V on the S-N fatigue, FCG, and Kc toughness have been determined at CWRU. Samples were processed by NASA ULI/STRI collaborators in the Keyhole, Lack of Fusion, and Process Window. 4PB/axial fatigue tests on both as-deposited, low-stress ground, and stress relieved conditions revealed a more limited fatigue/toughness-based process window than determined by metallographic/CT and process modeling. Defect character, size, location, and (likely) local microstructure at/near defects affected the potency of defects reducing the S-N performance in machined samples, while as-deposited surfaces produced significantly reduced S-N performance across P-V space regardless of process conditions. Quantification of fatigue initiating defects and those across the whole fracture surface was used to model the fatigue performance using various techniques, including Kitagawa plots. Nominally similar sized defects produced very different Kitagawa plots and fatigue lives, indicating the important role of local microstructure around such defects. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Additive Manufacturing, Mechanical Properties, Characterization |