Microstructures in nanocrystalline Ni–Fe alloys during cold-rolling were quantitatively investigated using synchrotron high-energy X-ray diffraction. It was found that rolling leads to an obvious reduction in the densities of both dislocations and twins and an increase in crystallite size. A huge dislocation flux flows through the grains during rolling, even though only a small fraction remains in the specimen after rolling. A mechanically induced relaxation of the initial high-excited state of materials was revealed.

Simultaneous Reductions of Dislocation and Twin Densities with Grain Growth during Cold Rolling in a Nanocrystalline Ni–Fe Alloy. L.Li, T.Ungár, Y.D.Wang, G.J.Fan, Y.L.Yang, N.Jia, Y.Ren, G.Tichy, J.Lendvai, H.Choo, P.K.Liaw: Scripta Materialia, 2009, 60[5], 317-20