Formation of nanostructures in commercial-purity titanium via cryorolling

Microstructure evolution in commercial-purity titanium during plane-strain multipass rolling to a true thickness strain of 2.66 at 77 and 293 K was quantified. Deformation at both temperatures was accompanied by twinning. At 77 K, twinning was more extensive in terms of the fraction of twinned grains and the duration of the twinning stage. Rolling to a true thickness strain of 2.66 resulted in the formation of a microstructure with a grain/subgrain size of similar to 80 nm at 77 K or similar to 200 nm at 293 K. The contribution of various mechanisms to the strength of titanium following rolling at 77 and 293 K was analyzed quantitatively. (C) 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.