About this Abstract |
Meeting |
MS&T23: Materials Science & Technology
|
Symposium
|
Additive Manufacturing: Design, Materials, Manufacturing, Challenges and Applications
|
Presentation Title |
Sensitivity of Surface Porosity in Powder Bed Fusion to Process Parameters |
Author(s) |
Corey L Smithson, Taylor Davis, Tracy W Nelson, Nathan Crane |
On-Site Speaker (Planned) |
Nathan Crane |
Abstract Scope |
Additive manufacturing offers inexpensive fabrication of complex parts at low volumes, but assuring part quality remains a challenge. The performance of powder bed fusion parts is sensitive to surface defects—especially under fatigue loading. However, most studies of porosity focus on bulk porosity. In this presentation, we will report the results of serial sectioning to measure the porosity as a function of depth from the down-facing surface. The results show that surface porosity is often substantially larger than the bulk porosity that is typically measured and tracked. The depth at which the porosity reaches bulk levels is highly sensitive to the build angle, support parameters, and scan parameters. Some combinations of parameters even produce secondary peaks of porosity below the surface. In these cases, finishing processes may expose regions with higher porosity than the native surface if insufficient material is removed. |