Temperature Dependence of Young's Modulus of Vitreous Germania and Silica

Abstract

The temperature dependence of Young's modulus of vitreous GeO2 has been determined by a dynamic resonance method from −195°C to 540°C. The modulus increases with increasing temperature from about −120°C to 400°C. Below and above this range the modulus decreases with increasing temperature. Young's modulus for vitreous SiO2 also increases from about −190°C to 1175°C and decreases with increasing temperature outside this range. In view of the similarity in structures and bond energies of these two materials, the similarity in the elastic modulus-temperature relations is believed to be significant; especially when contrasted with the lack of agreement in another commonly measured anharmonic property, thermal expansion.