Oxidation of Metallic Glasses Detected via Optical Characterizations

Oxidation of metallic glasses has been shown to be different from crystalline alloys due to the disordered atomic structures and far-from-equilibrium state, and quick characterization is required to reveal their early stage oxidation. In this talk, the oxidation behavior of bulk metallic glass by measuring the changes of optical constants via spectroscopic ellipsometry will be presented. Characterizations with X-ray diffraction, scanning electron microscopy, and thermogravimetric analyzer confirmed that the changes of pseudo-optical constants reflected not only the onset temperature at which the alloys underwent obvious oxidation, but also the subtle oxidation which was tedious to characterize. This study suggests a more efficient and accurate approach to understand the oxidation of metallic glasses, which can be extended as a high-throughput characterization method to mapping oxidation of crystallization of metallic glasses within a vast compositional space.