About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
|
Additive Manufacturing Fatigue and Fracture: Effects of Surface Roughness, Residual Stress, and Environment
|
Presentation Title |
Influence of Process Parameters on Fatigue Behavior and Defect Characteristics in LPBF Ti-6Al-4V |
Author(s) |
Austin Q. Ngo, David Scannapieco, Francisco Medina, Christian Gobert, Anthony Rollett, Jack Beuth, John Lewandowski |
On-Site Speaker (Planned) |
Austin Q. Ngo |
Abstract Scope |
Four-point bending fatigue testing was conducted on both as-built and machined surface LPBF Ti-6Al-4V mechanical testing specimens built with varying process parameters. Optimized and sub-optimal process parameter sets were selected to fabricate baseline builds and defect-induced builds, respectively. S-N fatigue data was generated for each process parameter set, and specimen fracture surfaces were imaged using OM and SEM. Fractographic analyses consisted of quantifying all defects on the fracture surface and identifying ‘killer’ defects responsible for fatigue crack initiation. Different types of process defects (i.e. lack of fusion, keyhole) were found to be more prevalent based on particular process parameter sets, which further influenced S-N curves. Specimen surface roughness contributed to differences in fatigue crack initiation behavior. The effects of process parameters on defect characteristics and the resulting S-N fatigue behavior will be discussed in the context of a defect-based Kitagawa-Murakami-type approach. |
Proceedings Inclusion? |
Planned: |
Keywords |
Additive Manufacturing, Mechanical Properties, Titanium |