ANALYZING THE PROCESS OF THE FORM CHANGE OF TUBULAR BLANKS BY HYDROMECHANICAL DEFORMATION

Abstract

The technological processes of hydro mechanical deformation of tubular blanks of aluminum alloys have found wide application in the automotive and aviation industries due to the high quality of manufactured products, relatively light weight and high specific strength.

Compared with the traditional processes of shaping, hydromechanical deformation of tubular blanks allows to get different structural elements of a fairly complex cross-sectional shape along the length of the pipe, which leads to lower costs and higher production efficiency. One of the main distinguishing features of hydromechanical deformation is the possibility of producing thin-walled structural elements of a rather complex cross-sectional shape, which may vary along the length of the product. This distinctive feature of the method, compared to extrusion, where the cross-sectional shape can also be quite complex, remaining constant along the length of the product, makes hydromechanical deformation the most promising, innovative technological process. At that, the integrity of the work piece is ensured at the same time, which is especially important for the assembly of stamped parts, costs decrease, and the production efficiency increases.

However, there are certain restrictions with regard to the degree of deformation that can be achieved, limiting the shaping of products with the given geometrical and technological characteristics. On this basis, in the present work, we have carried out analytical modeling of the process of shaping the tubular blanks by hydromechanical deformation taking into account the strain hardening with different applications of external forces. The relationship between the parameters in the power law of strain hardening and the mechanical properties of deformable materials is established. Analytical dependences are obtained and an estimate is given to the magnitudes of the external forces at which stable deformation occurs. The obtained analytical solutions and the established dependences between the hardening parameters and the mechanical properties of deformable materials allow to qualitatively estimate the necessary range of stable deformation.