Dislocation mediated plasticity in nanocrystalline Al: the strongest size
C Brandl, PM Derlet, H Van Swygenhoven
MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING | IOP PUBLISHING LTD | Published : 2011
Molecular dynamics simulations of nanocrystalline FCC metals revealed the strain rate dependence to be reflected in the critical resolved shear stresses for dislocation propagation. The strain rate and temperature dependence study is complemented by a stress and grain size dependence supporting consistently the importance of thermally activated dislocation mediated plasticity in the inverse Hall-Petch regime. A model is presented demonstrating that the strongest size can as well be explained on the sole basis of dislocation mechanisms. © 2011 IOP Publishing Ltd.