|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Bulk Metallic Glasses XIX
||On the True Stress-strain Curve of Metallic Glasses
||Amlan Das, Catherine Ott, Dinesh Pechimuthu, Robabeh Moosavi, Anja Waske, Mihai Stoica, Robert Maass
|On-Site Speaker (Planned)
Testing nominally identical bulk metallic glass (BMG) samples yields a large variety of post yielding behavior of which the fundamental origin remains unclear. This stands in stark contrast to the robust pre-yield behavior and a high Weibull modulus of the yield stress. Several studies have revealed that non-negligible internal micro-cracking (shear-band cavities) occurs in the inhomogeneous deformation regime (Acta Materialia 140 (2017) 206; Scripta Materialia 170 (2019) 29). To shed light onto the true-stress strain behavior, the strain-dependent evolution of internal damage is assessed along a full flow curve. We present a combined acoustic-emission and x-ray tomography study that tracks the internal shear-band cavity-growth as a function of strain, giving access to a true stress-strain curve. This data reveals an exponential growth of internal shear-band cavities with strain and a fractal cavity morphology. This unpredictable cavity growth process explains the large variability of post-yield behavior seen in the literature.
||Mechanical Properties, Machine Learning,