Ultrasonic behaviour of nanocrystalline Ni3Fe (15 nm)

Abstract

Ultrasonic attenuation due to phonon-phonon interaction, thermoelastic loss and dislocation damping due to screw and edge dislocations have been evaluated in nanocrystalline Ni3Fe (15nm), for longitudinal and shear waves, along <100>, <110> and <111> crystallographic directions of propagation and for various polarization directions. It has been found that ultrasonic behaviour of nanocrystalline face centred cubic resembles that of fcc bulk phase alloys and it has been found that like metallic alloys, contribution to total attenuation due to thermoclastic loss is negligible in comparison to attenuation due to phonon-phonon interaction. © 2006 IACS.