Estimation of thermal expansion coefficient of silicate glasses with compositional parameter

Thermal expansion parameter, alpha(p), which is based on the potential energy between cation-anion, has been proposed to estimate the thermal expansion coefficients of oxide glasses. alpha(pi) (i for the ith species) is defined as alpha(pi) = n(i)/n(i) - 1 (Z(+i)Z(-i)/r(eqi))(-1) by charge Z, Born exponent n and the equilibrium interatomic distance r(eq) calculated from the ionic radius. Ln this study, or, of multicomponent oxide glasses were calculated on the assumption that the additivity of alpha(p) was hold for the glasses, and the applicability of alpha(p) for the glasses was investigated. As a result, it mas revealed that many silicate glasses, including borosilicate and aluminosilicate glasses, could be divided by cation valence of network modifier oxide and an approximately linear relationship existed between the thermal expansion coefficient and alpha(p) in each division. It became possible to estimate the thermal expansion coefficient of silicate glasses accurately using the relations obtained in this study.