About this Abstract |
Meeting |
MS&T24: Materials Science & Technology
|
Symposium
|
Computational Materials for Qualification and Certification
|
Presentation Title |
Assessing the Impact of Melt Pool Geometry Variability on Lack-of-Fusion Porosity and Fatigue Life in Powder Bed Fusion - Laser Beam Ti-6Al-4V |
Author(s) |
Justin Patrick Miner, Austin Ngo, Tharun Reddy, Christian Gobert, Jack Beuth, Anthony Rollett, John Lewandowski, Sneha Prabha Narra |
On-Site Speaker (Planned) |
Justin Patrick Miner |
Abstract Scope |
Powder Bed Fusion - Laser Beam (PBF-LB) parts experience a significant decline in fatigue performance when process-induced defects are present. In this work, a decline in 4-point bend fatigue life was observed in PBF-LB manufactured Ti-6Al-4V coupons manufactured at constant power with increasing scanning velocity. Specifically, the decline in fatigue life observed with increasing scanning velocity corresponded with an increase in sparse LoF porosity at scanning velocities lower than expected. This work leverages high-resolution X-Ray micro computed tomography (X-μCT) to capture LoF pores with thicknesses greater than 7.5 μm in a scan volume greater than 250 mm. A modified LoF criterion was developed to account for melt pool geometry variability as it can generate LoF pores. The insights from this work provide guidance on performing rapid single track experiments and melt pool geometry characterization to systematically evaluate processing parameters that generate LoF pores, which, in turn, lower fatigue performance. |