Work hardening behavior of Mg-based nano-composites strengthened by Al2O3 nano-particles

The work hardening behavior of Mg and AZ31 Mg alloy containing nano-sized Al2O3 particles was studied. Interaction of dislocations with non-shearable nano-particles was considered as the governing mechanism of work hardening in the nano-composites. Different initial work hardening rates in Mg- and AZ31-base materials were correlated to their previous thermo-mechanical history. In comparison with the particle-free samples, nano-composites had all higher levels of work hardening rate and lower rate of dynamic recovery. The bilateral effects of nano-particles on work hardening capacity, caused by their potential grain refining capability and accommodating dislocations, are also discussed for a better understanding of the governing mechanisms in work hardening of the present nano-composite materials. (C) 2013 Elsevier B.V. All rights reserved.