EFFECTIVE TECHNOLOGIES OF SEVERE PLASTIC DEFORMATION

Abstract

Creation of new structural materials with new unique properties of metal remains one of the urgent tasks of modern materials science. In practice, it is possible to improve the properties of existing structural materials by grinding their structure to an ultra-fine-grained state. At the moment, one of the promising ways to obtain an ultra-fine-grained structure is the severe plastic deformation method (SPD). Most of the currently existing methods of implementation of the SPD have not been used in the real industrial sector due to the existing in this method of deformation of the disadvantage, which is the discreteness, i.e. the inability to process products of relatively long length and the need for a large number of processing cycles. And this determines the economic inexpediency of the introduction of this method in production. To solve the problem of introduction of the technology of production of ultra-fine-grained materials by SPD methods, we have developed a number of combined technologies of deformation, allowing to obtain rods of rectangular and circular cross-section of ferrous and non-ferrous metals with ultra-fine-grained structure. These processes include the following combined methods: "rolling-ECAP", “ECAP-drawing” "screw rolling-ECAP". As a result of numerous laboratory studies, to study the effect of the proposed methods of deformation on the microstructure evolution of various structural materials and change their properties, it was proved that the combined processes "rolling-ECAP" and "screw rolling – ECAP" have undeniable advantages over conventional equal-channel angular pressing, both in terms of more intensive grinding of grain and higher mechanical characteristics of the deformable metal in one cycle of deformation, and in terms of the possibility of obtaining long blanks.