|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Coupling Experiments and Modeling to Understand Plasticity and Failure
||Strain Field Mapping and Modeling Around Laser-induced Keyhole Defects in Ti-7Al under Cyclic Loading
||Rachel Lim, Yufeng Shen, Christopher Kantzos, He Liu, Robert Suter, Anthony Rollett
|On-Site Speaker (Planned)
Keyhole defects were introduced to a sample of α-Ti-7Al using a custom laser setup. High-energy x-ray diffraction microscopy (HEDM), a non-destructive 3-D characterization technique, was used to track microstructural evolution under cyclic loading. Near-field HEDM (nf-HEDM) provides grain morphology and orientation, while far-field HEDM measures the strain state of each grain. This data was registered with an x-ray micro-tomography reconstruction to create a full 3-D microstructural reconstruction. The initial eigenstrain field created by the solidification shrinkage of the melted material was calculated using thermos-elastic fast Fourier transform-based modeling and used as an input for elasto-viscoplastic modeling using MASSIF to calculate the residual elastic strain fields. We perform grain-by-grain analysis to track strain evolution under cyclic loading. Initial results show a decrease in residual elastic strain over the first couple of cycles followed by an increase in the strain distribution as well as a localization of strain around the pores.
||Planned: Supplemental Proceedings volume