On the plasticity of Al-Cu-Fe quasicrystals

A technique of repeated load relaxation tests (RLRT) has been used to evaluate microstructural evolutions and activation volumes of Al-Cu-Fe quasicrystals deformed in compression tests performed at constant strain-rate. The post-relaxation behaviour after reloading at constant strain-rate and the evolution of correction terms, measured by RLRT in order to account for microstructural evolution, confirm that Al-Cu-Fe plasticity is controlled by a strain-dependent thermally activated mechanism. Activation volumes measured in the hardening and softening stages of the yield point reveal that the same mechanism controls plastic deformation.