About this Abstract |
Meeting |
2020 TMS Annual Meeting & Exhibition
|
Symposium
|
Fatigue in Materials: Fundamentals, Multiscale Characterizations and Computational Modeling
|
Presentation Title |
Micromechanics-based Effect of Defects Models for Ellipsoidal Anomalies |
Author(s) |
James Sobotka, R. Craig McClung, Michael Enright |
On-Site Speaker (Planned) |
James Sobotka |
Abstract Scope |
This presentation introduces a novel methodology to characterize the effect of defects on fatigue lives. We approximate defects ellipsoidal anomalies in a homogenous, linear-elastic continuum loaded by arbitrarily far-field stresses. The geometric features of the anomaly concentrate stresses, and these stresses may be determined using Eshelby approaches. Furthermore, we combine these stresses with Taylor’s theory of critical distances to incorporate a material-dependent length scale into fatigue predictions. This presentation summarizes predictions from this framework, including exact analytical expressions for stresses near spherical pores, failure envelops analogous to Kitagawa diagrams, and fatigue-life reductions due to ellipsoidal anomalies. These results show the effect of stress state, pore size, and pore shape on fatigue life predictions. At this time, these predictions are limited to empty pores, but the framework presented here is easily extensible to anomalies due to stiffness mismatch and pores with entrapped gas as in additively manufactured components. |
Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |