Viscoelastic analysis of RFDA measurements applied to oxide glasses

International audience; The Resonance Frequency and Damping Analysis (RFDA) is now a common experimental technique to measure the elastic moduli of materials vs. temperature. Nevertheless, the elastic moduli are calculated assuming that the frequency measured is the natural one, not impacted by any damping. In oxide glasses, a significant damping occurs below the glass transition temperature, and it may impact the frequency measured, the elastic moduli calculated, as well as the estimated glass transition temperature. We show here, using the equations of linear viscoelasticity, how we can know if the frequency measured is significantly lowered by damping, and how we can estimate the natural frequency to calculate the correct elastic moduli, only from the data provided by the RFDA the frequency measured and the damping. © 2020 Elsevier B.V.