Internal friction phenomenon in relation to the properties of point defects in metals

Abstract

Point defects can give rise to anelastic and internal friction phenomena, if several specific conditions are fulfilled. Conversely, the observation of these phenomena gives very useful information concerning the defect concentration, mobility and symmetry that are simultaneously detected. In metallurgical research, hetero interstitial investigations, performed by means of these techniques, reveal the impurity affinities and the precipitation kinetics. In radiation damage research, internal friction gives evidence of a free migrating defect in stage IE of bcc and hcp metals, and in stage III of nickel and copper. Close pairs of surprising stability are often mentioned.