Yttria substitution effect of tantalate aluminosilicate glasses with ultra‐high Young's modulus

We report novel oxide glasses that are compatible with ultra‐high Young's modulus (∼150 GPa) and a small coefficient of thermal expansion (∼5.0 ppm/K). These glasses were prepared using a conventional melt‐quenching technique. The viscosity–temperature relation provides the reshaping temperature for the stiff and less dilated oxide glasses. The origin of the ultra‐high Young's modulus is the inclusion of Y 2 O 3 as well as five‐ and six‐coordinated alumina oxide and Ta 2 O 5 , which has a large ionic packing ratio due to higher oxygen coordination numbers. On the other hand, the small thermal expansion coefficient originates from including Ta 2 O 5 and SiO 2 with large dissociation energy due to strong bonds.