Mixed alkaline‐earth effects on several mechanical and thermophysical properties of aluminate glasses and melts

Abstract Owing to heterogeneous nucleation at the melt‐crucible interface, it is difficult to access the dynamic and physical properties of supercooled liquids of poor glass formers when using a conventional melting technique. To avoid the interface nucleation, we apply a containerless aerodynamic levitation laser‐melting technique to measure the viscosity, density, and surface tension of a poor glass‐forming system, ie, the mixed alkaline‐earth aluminate melts. The temperature and composition (Ca/Sr) dependence of thermal‐physical properties are investigated on both thermodynamically stable and metastable supercooled melts. In addition, the levitation laser‐melting technique is used to quench the melts to glasses, and then the mixed alkaline‐earth effects are investigated on Vickers micro‐hardness and glass transition temperatures. By comparing the chosen silicate and aluminate series, we have identified weaker mixed alkaline‐earth effects in aluminate series than those in silicate series, and this difference could be attributed to the different structural roles of alkaline‐earth elements in two glass series.