A comparison between numerical and analytical modeling of ECAP

Document Type: Research Paper

Authors

1 Khajenasir University of Technology

2 K.N. Toosi University of Technology

Abstract

Recent developments in nanostructured products draw considerable attention to ultrafine grained materials. These materials are normally manufactured by different severe plastic deformation (SPD) methods. In the present study, analytical models and finite element method (FEM) are used to calculate strain imposed to a specimen that was deformed by equal channel angular pressing (ECAP). In addition, strain inhomogeneity in term of coefficient of deviation (CV) for an aluminum alloy (AA6101) processed under ECAP was calculated. Dies with 90º, 105º and 120º intersecting angles were modeled based on FEM. Furthermore, the effect of friction on force-displacement curves was investigated using analytical and numerical approaches. Moreover, the energy loss that is due to friction was computed. Strains calculated by FEM for different die angles were identical to those evaluated by analytical models. Based on numerical and analytical models, it has been shown that strain inhomogeneity increases when the angle between two channels decreases.

Keywords


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