Deformation processes during tensile straining of ultrafine/nanograined structures formed by reversion in metastable austenitic steels

The deformation behavior of ultrafine/nanograined (UFG/NG) structures during tensile straining has been examined by electron microscopy in metastable austenitic steels. Special fine-grained structures were obtained by controlled phase-reversion annealing of heavily cold-worked metastable austenite, leading to an excellent tensile strength–ductility combination. Twinning and dislocation glide were identified as the primary deformation mechanisms operating in UFG/NG structures.