| About this Abstract |
| Meeting |
MS&T21: Materials Science & Technology
|
| Symposium
|
Additive Manufacturing: Processing, Microstructure and Material Properties of Titanium-based Materials
|
| Presentation Title |
Fatigue Fracture Surface Defect Quantification for LPBF Additively Manufactured Ti-6Al-4V |
| Author(s) |
David S. Scannapieco, Austin Q Ngo, Collin Sharpe, Hunter Taylor, Ryan Wicker, Joseph Pauza, Anthony Rollett, John Lewandowski |
| On-Site Speaker (Planned) |
David S. Scannapieco |
| Abstract Scope |
Keyhole, lack of fusion (LoF), and the process window are AM parameter regimes that form unique defects in as-built Ti-6Al-4V. The impact of each process regime’s defects on S-N fatigue and fracture surface morphology has been quantified by measuring size, shape, and orientation of every defect on multiple fatigue fracture surfaces. This novel dataset exceeds 10,000 defects and enables comparison between the effects of different process regimes on S-N and fracture surface characteristics. This work shows the LoF regime to exhibit the largest defects, often interconnected, and highest defect density. Extreme value analysis (EVA) was used to evaluate the size and probability of critical defects on the fracture surfaces. The fracture surfaces revealed an increase in defect density on going from the fatigue to the overload region, likely due to an increased plastic zone size and sampling volume. The implications of these results on S-N fatigue behavior will be discussed. |