Grain Boundaries in Ball-Milled Iron
          A new approach based on the Embedded Atom Method is applied to model the structure of grain boundaries in nanostructured powders. A Monte-Carlo scheme, namely various modifications of the well established simulated annealing Metropolis algorithm, is used to obtain realistic structures of twisted and tilted double and triple grain boundaries as a function of the relative disorientation of the grains. A few parameters have to be assumed. Results indicate a new configuration which is closer to the bcc structure than the fcc one in the case of iron nanopowders.