The collective pinning of dislocations was introduced into disordered quenched solid solutions, and the macroscopic mechanical response to a small, direct or alternating, applied stress was calculated. This constituted a generalization of the Granato-Lücke string model, and could self-consistently describe short-range and long-range dislocation motion. Under direct applied stresses, long-distance dislocation creep exhibited avalanche features at the microscopic level. These resulted in macroscopic non-linear, so-called glassy, velocity-versus-stress characteristics. Under alternating conditions, the model predicted (in addition to anelastic internal friction relaxation in the high-frequency regime), a linear internal friction background which remained amplitude-independent down to a cross-over frequency; where it entered a strongly non-linear internal friction regime.

Internal Friction and Dislocation Collective Pinning in Disordered Quenched Solid Solutions G.D'Anna, W.Benoit, V.M.Vinokur: Journal of Applied Physics, 1997, 82[12], 5983-90