Temperature dependence of the viscoelastic response of In, Sn and In–Sn alloys

The elastic modulus and the internal friction of Sn and the gamma-In–Sn phase are measured with a two-component piezoelectric oscillator at 50 kHz in the temperature range from 296 to 390 K. For both materials the viscoelastic responses at strains below 10-6 are described in terms of a Debye peak characterized by an effective activation enthalpy of 54.8 and 20.4 kJ/mol, for Sn and the gamma-In–Sn phase, respectively. Due to their higher damping, the dynamic mechanical responses of In and the eutectic In–Sn were measured with a three-components piezoelectric resonator between 296 and 390 K at 50 kHz. The temperature dependence of the internal friction of the eutectic can be well described in terms of a single relaxation time with an effective activation enthalpy of 38 kJ/mol. Indium is not only amplitude dependent but also exhibits thermal hysteresis.