Sound Attenuation at High Temperatures in Pt

Ultrasonic attenuation due to phonon–phonon interaction and thermoelastic loss was evaluated in VIII group transition metal Pt in a wide temperature range (100 K to 1500 K) for longitudinal and shear waves along 〈100〉, 〈110〉 and 〈111〉 directions and for shear waves polarised along different directions. Electrostatic and Born–Mayer potentials were used to obtain second and third order elastic constants, taking nearest-neighbour distance and hardness parameter as input data. Second and third order elastic constants data obtained at different temperatures were used to obtain Gruneisen parameters and non-linearity or anisotropy parameters which in turn were