A model of plasticity controlled by the pure climb motion of dislocations was proposed and compared with the mechanical properties of icosahedral AlPdMn. This model took into account the chemical stress due to an out-of-equilibrium average concentration of vacancies, and the difficult nucleation of jog-pairs on climbing dislocations. It accounted for several unexplained properties of AlPdMn, namely a high strain-hardening at yield, a steady-state flow stress twice higher than the elastic limit, and two-stage relaxation curves. It also explained values of the stress–strain rate sensitivity that were larger than expected a priori, and activation energies larger than the self-diffusion one. The model could also be applicable to the high-temperature deformation of crystals.

Dislocation-Climb Plasticity - Modelling and Comparison with the Mechanical Properties of Icosahedral AlPdMn. F.Mompiou, D.Caillard: Acta Materialia, 2008, 56[10], 2262-71