The dislocation amplitude-dependent friction of 5N-purity polycrystalline material was investigated at 7 to 300K using vibrational strain amplitudes of 10-7 to 10-4. The samples were in the annealed or deformed (quasi-static, shock, ultrasonic) states. The amplitude-dependent friction was a multi-stage effect at these temperatures and vibration amplitudes. An analysis of the amplitude-temperature spectra of the amplitude-dependent friction permitted a separation of the components which were due to interactions between dislocations, to interactions of dislocations with pinning points, and to pure dislocation relaxation (interaction of dislocations with the Peierls stress). The amplitude-dependent friction was observed to depend non-monotonically upon the initial quasi-static strain, as determined by strain hardening and recovery processes.

Influence of Temperature and Strain on the Amplitude-Dependent Internal Friction of High-Purity Aluminum. S.N.Golyandin, K.V.Sapozhnikov, J.A.Emelyanov, A.B.Sinani, S.P.Nikanorov, S.B.Kustov, W.H.Robinson: Fizika Tverdogo Tela, 1998, 40[10], 1839-44 (Physics of the Solid State, 1998, 40[10], 1667-71