About this Abstract |
Meeting |
2022 Annual International Solid Freeform Fabrication Symposium (SFF Symp 2022)
|
Symposium
|
2022 Annual International Solid Freeform Fabrication Symposium (SFF Symp 2022)
|
Presentation Title |
Use of Extreme Value Statistics for Establishing Process-Porosity-Fatigue Relationships in Laser Powder Bed Fusion Additive Manufacturing |
Author(s) |
Sneha Prabha Narra |
On-Site Speaker (Planned) |
Sneha Prabha Narra |
Abstract Scope |
The process-induced defects and microstructural inhomogeneities in laser powder bed fusion processed parts contribute to undesirable variation in fatigue properties. We introduce a process qualification framework for Ti-6Al-4V that involves process mapping, characterization, fatigue testing, and statistical analysis. We apply concepts from the statistics of extremes to model the upper tail of the pore size distribution, a major determinant of fatigue performance and scatter. During analysis, we apply the peaks-over-threshold method to identify the upper tail of a pore size distribution and then estimate the critical defect size in the material. Furthermore, we present the effects of varying processing parameters on the critical defect size and compare those with crack initiating defect size and fatigue life from four-point bending fatigue tests. The results demonstrate the existence of a fatigue-based process window and accurate estimation of critical defect size determining the fatigue life. |
Proceedings Inclusion? |
Definite: Post-meeting proceedings |