Computer simulation of the interaction between an edge dislocation and Cu precipitates in bcc iron

The molecular dynamics method was used to determine the energy of the interaction between a 1/2 111] (110) edge dislocation and a Cu precipitate in bcc Fe. It was shown that three ranges of precipitate dimensions, characterized by different types of hardening, can be distinguished as a dislocation crosses over a precipitate. It was found that maximum hardening was due to the structural instability of the particles relative to the bcc—9R transformation, with this instability resulting from the stress fields produced by a dislocation.