|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Integrative Materials Design III: Performance and Sustainability
||Fatigue Crack Growth Modeling and Mechanisms in Al and Ni Engine Materials under Hot Compressive Dwell Conditions
||Xiang Chen, Diana A. Lados, Richard G. Pettit, David Dudzinski
|On-Site Speaker (Planned)
Fatigue crack growth (FCG) under Hot Compressive Dwell (HCD) conditions, a special case of creep-fatigue occurring under compressive stress, is an important failure mode in many high temperature applications. Tensile residual stresses building up at the crack root are considered a key factor contributing to FCG under HCD conditions. To understand and quantify this effect, a physics-based model was developed, in which the residual stress contributions are added to the elastic and plastic responses of the material to predict the behavior. In contrast with the existing complex models, this fracture mechanics approach is simple, easy to apply, and generates good predictions. Results from both isothermal and thermal-cyclic tests were analyzed and compared. Comprehensive SEM and TEM studies were also performed to understand HCD effects at the microstructural scale of two engine alloys (cast Al-319 and IN718), and recommendations will be given to optimize the materials’ microstructures for high temperature applications.
||Planned: Supplemental Proceedings volume