| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Fatigue in Materials: Fundamentals, Multiscale Characterizations and Computational Modeling
|
| Presentation Title |
Probing Fatigue Crack Growth and Initiation Using Microscale Specimens |
| Author(s) |
M. H. Shahini, A. Kaveh, B. Zhang, X. Zhang, Wen Jin Meng |
| On-Site Speaker (Planned) |
Wen Jin Meng |
| Abstract Scope |
Using Ni alloys made by laser powder bed fusion additive manufacturing, we demonstrate quantitative assessments of fatigue crack growth and initiation (FCG/FCI) through cyclic bending of pre-notched cantilevers with cross-sectional dimensions of ~25 um x ~25 um. We show that cyclic bending of such pre-notched cantilevers can sense the threshold regime and the Paris-law regime of FCG quantitatively and measure the number of cycles needed for crack initiation from focused ion beam machined pre-notches, despite the small specimen size. The fabrication of such microscale test specimens enables control of the direction of fatigue crack propagation with respect to a given microstructure, while avoiding the inclusion of volumetric defects within the test volume. Significant differences in FCG behavior were observed when the direction of crack propagation was switched from being parallel to the build direction to being perpendicular to it. The effect of loading frequency on crack initiation can be evaluated. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Mechanical Properties, Characterization, |