Study On Equal Channel Angular Pressing Simulation Of Magnesium Alloy AZ31 By Finite Element Method

Much more attention has been paied to Equal Channel Angular Pressing (ECAP) in recent years because it can prepare big block materials with ultra-fine grains. In this paper, ECAP of magnesium AZ31 has been simulated by finite element method (FEM), the influence of friction condition, extrusion temperature and speed as well as die's radius on load and distribution of stress and strain field have been studied. The results show that the peak load and stable load fall down with while the temperatures increase. The stable load goes up while extrusion speed increase. The pressing-load curve could be simple divided into two phases by a peak load when frictions rise: the swift ascend and descend phases. The pressing-load curves don't be influenced obviously by die's radius. The pressing-load curve of first and second are similar, and the change of maximum load aren't explicit when materials are extruded by route A, route B and route C.The self-design "Complex Die Method" (CDM) which compound the ECAP consequence two passes into one process is adopted. 2D simulation has been applied to two-passes extrusion of route A and route C and 3D simulation has been applied to two-passes extrusion of route B_C, the changes of stress, strain and load through two passes extrusion have been gained. The uneven distribution of deformation of materials increase when extruded by route A, after the first pass, the uniform strain field is two-thirds of whole materials, and one-half after second pass. After two passes, the maximum total plastic strain increase from 2.218 to 3.232 and plastic strain in the uniform strain zone increase from 1.392 to 2.371. The uniform of strain amend after consequence two-passes extrusion by route C , the maximum total plastic strain increase from 1.875 to 2.915 and plastic strain in the uniform strain zone increase from 1.177 to 2.915. After two passes extrusion by route B_C, the maximum total plastic strain increase from 1.927 to 3.450, and plastic strain in the uniform strain zone increase from 1.166 to 2.171.