Make nanostructured metal exceptionally tough by introducing non-localized fracture behaviors

A new method for manufacturing nanomaterials with high ductility on a large scale is reported here. Based on surface nanocrystallization and warm co-rolling technologies, the resulting material amazingly exhibits high strength and exceptional ductility. Stainless steel was selected to demonstrate the extensibility of our approach. The yield strength (878 MPa) is more than double that of the monolithic material. The elongation to failure (48%) triples comparing with the material with the same yield strength obtained by work hardening. (C) 2008 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.