Energetics of radiation defects in Fe-based austenitic alloys: Atomic scale study

Energetics of typical radiation defects observed in austenitic stainless steel of 304L type has been characterized in the model FeNi10Cr20 alloy by means of atomistic simulations employing a set of interatomic potentials specially derived to reproduce main features of 304L steel. The following defects have been considered: dislocation loops of both interstitial and vacancy nature, stacking fault tetrahedron, perfect loops and voids. The formation energy of these defects has been calculated at 0 K and the obtained results have been compared with the prediction of the elasticity theory. A good agreement has been found in all the cases except for the hexagonal Frank loop, whose sides have splitted into 1/6〈1 1 2〉 partial dislocations, thus lowering the total formation energy. High temperature annealing, performed using molecular dynamics simulations, has proven that the considered defects are thermally stable in the temperature range 300-1200 K.