As it is known, high pressure torsion (HPT) leads to formation of ultrafine-grained states with a unique complex of physical and mechanical properties [1]. However, the problem of homogeneity of structure and texture, being formed at different distances from the torsion axes and corresponding to the areas with a different accumulated strain values, have still remained unsolved.
The current work presents the results of the conducted experimental X-ray structural studies of the preferred orientations homogeneity in copper billets, subjected to HPT. HPT was realized by deforming of disk-shaped billets 10 mm in diameter and 0.7 mm thick under the imposed pressure of 5 GPa with a number of rotations, equal to 1, 5 and 10, at room temperature. Four selected areas, located at equal distances from each other in one of the billet’s radii, were investigated. The size of areas consisted 0.6 mm in diameter. The results are presented in a form of pole figures (PF) (111), (110) as well as volume fractions of the main texture components LaboTex texture software was used for calculations and graphic presentation of the obtained results [2].
It was established that the crystallographic texture in the initial state is rather chaotic, but it is homogeneous along the billet’s radius. The preferred orientation, which can be described as a pure shear texture is formed during the process of HPT after a different number of rotations. At the same time, one may observe increasing the texture intensity of the main texture maxima with raising the number of rotations and smearing the texture alongside with retiring from the billet’s center.
1. Valiev R.Z., Islamgaliev R.K., Alexandrov I.V., Bulk nanostructured materials from severe plastic deformation, Progr. Mater. Sci. (2000) 45, pp. 103-189.
2. Pawlik K., Ozga P.: LaboTex: The Texture Analysis Software, 'Göttinger Arbeiten zur Geologie und Paläontologie', SB4, 1999.
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