In this paper, a discrete-obstacle and a collective model of solution harde
ning are compared. In the former model, interaction between a dislocation a
nd a single solute is considered, while in the latter, the dislocation line
interacts collectively with a row of solutes. Model predictions are compar
ed with experimental data for Cu-Mn and Nb-Mo single crystal systems and a
Ni-C polycrystal system. The collective model gives better results for the
two fee systems while the bcc system cannot be explained well by either. Th
e limitations and modelling capability of the two approaches are discussed
with respect to the experimental information. (C) 2001 Elsevier Science B.V
. All rights reserved.