Substitution effect of metal oxide on the elastic modulus of aluminoborate glasses

抄録

The remarkable diversity of the physical properties of glass is primarily attributed to its ability to incorporate various chemical species. Glass is a solidified liquid, i.e., a monolithic material with a “randomly” connected network; therefore, its properties can be tailored through compositional design. Titanium dioxide (TiO₂), which is classified as an intermediate oxide, affects the structural, thermal, optical, and mechanical properties of glass. Moreover, the valence of titanium influences the optical properties of glass and its thermal stability against the precipitation of crystallites. This study investigates the substitution effect of TiO₂ on aluminoborate glasses with high hardness and Young’s modulus. The glasses are prepared using a conventional melt-quenching method. Ti-free glasses possess high transparency in the visible region, and the coefficient of thermal expansion correlates with those of the substituted metal oxides. Both the thermal stability against crystallization and the mechanical properties change with composition. Although structural data for B₂O₃ and Al₂O₃ in all glasses are not available, the elastic properties may mainly depend on the dissociation energies of the metal oxides.