Ultrafine-Grained Metals

Ultrafine-grained (UFG) metallic materials are at the cutting edge of modern materials science as they exhibit outstanding properties which make them very interesting for prospective structural or functional engineering applications. Due to the progress in severe plastic deformation techniques during the last decade, ultrafine-grained microstructures are no longer only restricted to easy to deform single-phase materials, but can also be introduced in complex and hard to deform alloys of technological relevance. Nowadays it is of course clear that not only the hardening effect by the well-known Hall-Petch law is of high importance in UFG materials, but many other issues also come into play. This Special Issue on ultrafine-grained metals covers a broad range of research activities in that field. Fifteen articles have been selected for this issue addressing manifold topics such as new developments in severe plastic deformation techniques, advances in modeling and simulation of the severe plastic deformation processes, mechanical properties under monotonic and cyclic loading of homogenous and graded UFG structures and, related to that, dominating deformation mechanisms in UFG materials. Furthermore, advances and strategies for high conductivity materials by introducing UFG structures; the correlation between severe plastic deformation parameters and the resulting materials properties; and peculiarities in the corrosion behavior of UFG materials, have been addressed. The 15 articles reflect, on the one hand, the variety of state of the art research activities in the field and, on the other hand, form the spearhead of current advances. The articles are briefly summarized as follows: