|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Fracture: 65 Years after the Weibull Distribution and the Williams Singularity
||Grain and Sub-grain Level Strains ahead of an Evolving Fatigue Short Crack as Measured by X-ray Techniques
||Diwakar Naragani, Michael Sangid, Paul A Shade, Peter Kenesei, Hemant Sharma
|On-Site Speaker (Planned)
High variability in crack propagation directions and growth rates renders comprehension and prediction of fatigue short crack growth complicated. In this study, we employ a suite of characterization techniques based on high energy synchrotron x-ray experiments. Absorption contrast tomography is used to resolve the intricate 3D path of the crack through the bulk of a Ni-based superalloy specimen under cyclic loading. Initial near-field high energy diffraction microscopy (HEDM) is used to generate high resolution grain maps with intragranular orientation spread and grain boundary positions in conjunction with the crack path. Cyclic loading is periodically interrupted to conduct far-field HEDM to determine the centroid position, average orientation and average lattice strain tensor for each grain. Reciprocal space maps are used to examine the complete micromechanical state of grains next to the crack tip. Findings are used to study short crack growth relative to the local microstructure in Ni-based superalloys.
||Planned: Supplemental Proceedings volume