Mechanical and thermophysical properties of La2O3.Y2O3.Al2O3 glasses and melts

Over the past few decades, rare earth aluminate glasses have attracted widespread attention in different fields, owing to remarkable electric insulation performance, high refractive index and high transmittance. In this work, we firstly investigate the mixed rare earth effect by partial substitution of lanthanum for yttrium oxides in aluminate glasses by a contactless aerodynamic laser heated levitation technique. Different with previous reported mixed modifier glasses, the result of the aluminate glasses manifest a near‐linear trend in Vickers hardness with the rare earth substitution. Using Raman spectroscopies to insights into the structural these glasses, we demonstrate that the high crack resistance (CR) of aluminate glass is stronger correlation with the medium-range structure. In addition, we found the mixed rare earth effects on the glass transition temperatures, which show is stronger correlation with the medium-range structure order (peak width at half height of the lower-frequency region). In the aluminate glasses, the mixed rare earth have the Al–O and La–O bond distances diversity, which consequently increase the coefficient thermal expansion in aluminate melts. However, the isokom temperatures in aluminate melts exhibit a linear trend with composition.