|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Bulk Metallic Glasses XIII
||Structural Heterogeneity Induced Plasticity in Metallic Glasses
||Yanfei Gao, Hongbin Bei
|On-Site Speaker (Planned)
It has been demonstrated that the fracture toughness decreases sharply for bulk metallic glasses transitioning from as-cast to annealed states. We have utilized a nanomechanical testing method to measure the stresses for the onset of plasticity, and developed a stochastic statistical model to characterize the structural heterogeneity (including defect density and strength) inside the metallic glasses. The synergy between experimental and theoretical works found that, with increasing the structural relaxation, the defect density drops by two orders of magnitude, and correspondingly the fracture of metallic glasses changes from a significantly plastic (metal-like) mode to an extremely brittle one (fragile glass). Strain field fluctuations and evolutions measured by digital image correlation technique provide complementary information on the roles played by the structural heterogeneities. These conclusions make a quantitative relationship between microstructural heterogeneity and macroscopic ductile-to-brittle transition.
||Planned: A print-only volume