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Cross wedge rolling is a shaping forming new process that rolling to the radial depressed, axial extension and horizontal expansion. After years of development, it has become a broad shaft parts of the processing methods. However, cross wedge rolling is a complex three-dimensional forming processes, and the deformation mechanism is very complex, it is difficult to get the internal stress and strain rolling accurate information under the current experimental conditions, so it is lack of understanding the nature for the metal flow patterns and variability characteristics in the rolled forming process. With the development of computer technology in recent years, using numerical simulation method to study the cross wedge rolling up has developed gradually, in this paper, using the numerical simulation methods to study the metal flow pattern and deformation characteristics in process of shaft forming, understand laws and mechanism of forming rolled have a great significance.This article is based on the theory of cross wedge rolling, using large scale finite element software ANSYS/LS-DYNA to research the forming mechanism of cross wedge rolling. The results of their research for the forming part of the cross wedge rolling, improving part quality and avoiding rolling inside the hollow defects have important theoretical significance and practical value.This paper first reviews the development and applications of the cross wedge rolling technology, as well as the status of the field of research at home and abroad, and then briefly introduced the rolling principle of cross wedge rolling, the general principles of mold design, elastic-plastic finite element related theories. In the main part of papers, according to the geometric relationship between the space of the model of the cross wedge rolling, it determines the parameters of the mold between the parameters of expression, establishes the parametric solid models of the model of the cross wedge rolling, and then inducts the establishment parametrization model in the ANSYS/LS-DYNA software, through the selection of the mold as well as the rolling element type, the determine of material models, the division of the grid, the definition of contact, constraints imposed by the initial conditions, setting, loading and so on, constructed finite element model of the cross wedge rolling system, carried out a numerical simulation of cross wedge rolling, by means of ANSYS/LS-DYNA general purpose post processor, has been rolled in the rolling process of wedging paragraph, stretcher segment cross section and longitudinal section the stress and strain field distribution and characteristics of rolling deformation, reveals the rolling deformation characteristics and the metal flow law. Finally by choosing rolling within the four feature points, using the general purpose processor the post processing functions of the ANSYS/LS-DYNA software, rolls four feature points within the time course of stress-strain curves, obtaining the alternating stress and strain are the main hollow defects that rolling occurred center porosity and lacking of hollow.
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