Interaction of 〈1 0 0〉 loops with Carbon atoms and 〈1 0 0〉 dislocations in BCC Fe: An atomistic study

We apply atomistic simulations using the so called ‘metallic-covalent bonding’ interatomic model for the Fe–C system to study mobility of 〈1 0 0〉 interstitial dislocation loops, known to form in Fe and Fe-based ferritic alloys under irradiation, and their interaction with Carbon atoms. Carbon atoms represent an effective trap for the 〈1 0 0〉 loops with a binding energy of the order of 1 eV. The mobility of the loops is studied using the dislocation – loop drag model. From this model the activation parameters are identified and discussed.

► We studied <100> interstitial loops in Fe using the metallic-covalent bonding potential. ► Interaction of <100> loops with Carbon and <100>{011} dislocation has been addressed. ► Carbon is attracted to the loops with binding energy of 1.0 eV. ► Square loops with sides along <110> can be dragged by the edge dislocation. ► A range of dislocation velocity, temperature and spacing for the drag are determined.