Structure Refinement and Bauschinger Effect in fcc and hcp Metals

Although the Bauschinger effect has been investigated in some detail various materials, number of articles on grain size is extremely limited, and current nanostructured materials it practically absent. Since such are considered as promising for structural applications, important to understand their mechanical behavior under conditions changing direction deformation, and, therefore, necessary study its dependence size. The was by a single exemplary method tensile compression commercially pure hcp titanium fcc copper, with different sizes range from hundreds microns nanometers. change performed structure refinement severe plastic deformation using equal-channel angular pressing subsequent annealing. It established that, both increases decrease size, degree permanent strain duration exposure between forward reverse deformation. signs parameter copper opposite. relationship nature hardening softening ultrafine-grained state discussed.