| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Environmentally Assisted Cracking: Theory and Practice
|
| Presentation Title |
An Inverse Analysis of the Fatigue Crack Process Zone From Far Field Measurements |
| Author(s) |
Yanfei Gao, Huck Beng Chew |
| On-Site Speaker (Planned) |
Yanfei Gao |
| Abstract Scope |
A weak interface model with a predefined traction-separation relationship (denoted as the cohesive zone law), when embedded in a bulk solid, is oftentimes adopted to simulate the crack advancement and thus determine the crack resistance under either monotonic or cyclic loading conditions. To-date, various types of loading-unloading irreversibility and hysteresis are only presumed in the cohesive zone law for fatigue crack growth, but without any direct determination from experimental measurements. Using a fine-grained Mg alloy and synchrotron X-ray diffraction (S-XRD) measurements with a sub-millimeter beam, in situ lattice strain mapping can be obtained. We then develop an inverse analysis to extract the fatigue-crack cohesive zone which turns out to exhibit a bilinear unloading and reloading behavior. Distinctively different than all prior works, this particular form suggests the origin of irreversibility be primarily from crack-surface oxidation and the hysteresis from dislocation plasticity in surrounding grains. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Mechanical Properties, |