Deformation curves in uniaxial tension and compression at 300K were studied for commercial-grade and ultrafine-grained samples having various nanostructures. The latter were produced by severe plastic deformation using equal channel angular pressing and subsequent heat-treatment. It was found that differences between the yield stresses in tension and compression (SD-effect) depended upon the structural state and upon the texture of the samples. The magnitude of the SD-effect differed considerably for samples which were strained along directions that were parallel and perpendicular to the equal channel angular pressing axis. The effect of the texture upon the yield stress, under uniaxial compression, was studied at 300, 77 and 4.2K.

The Contribution of Grain Boundary Dislocations to the Plastic Deformation of Nanostructured Titanium from the SD-Effect of the Yield Stress. E.D.Tabachnikova, V.Z.Bengus, V.V.Stolyarov, G.I.Raab, R.Z.Valiev, K.Csach, J.Miskuf: Materials Science and Engineering A, 2001, 309-310, 524-7