Pd-based metallic glass with a low glass transition temperature

In this study, a Pd40Cu20Ge40 metallic glass has been introduced as a novel prototype of Pd-based metallic glasses. The Pd40Cu20Ge40 glass exhibits glass transition at 52 °C. The glass transition temperature reduced by the melting point of most glasses is roughly 0.5 or 0.6 but that of the Pd40Cu20Ge40 glass is only 0.36, which is considerably lower than those of other metallic glasses. Specific temperature measurement, microstructural observation, viscosity measurement and demonstration of viscous flow forming were performed to confirm that the novel material presented is a glass. From viewpoint of the constraint on the motion of molecules or clusters in glasses, new categorization of glasses has been proposed.