Tensile Properties and Fracture Characteristics of ECAP Processed Al and Al-Cu Alloys

In the present paper, billets of pure Al, and cast-homogenized Al-2 wt.%, 3 wt.%, and 5 wt.% Cu alloys were successfully processed by equal channel angular pressing (ECAP) up to 10 passes without fracture at room temperature using a die with a channel angle of 110 degrees. Giant strains imposed on workpieces lead to extreme dislocation densities, microstructural refinement, and finally ultrafine grained materials. Tensile tests were employed to examine the fracture modes and fracture surface morphologies of the ECAP-processed Al and Al-Cu alloy samples. In particular, the effects of the number of ECAP passes and the Cu content were investigated.X11922sciescopuskc

Plastic Flow and Strain Homogeneity of an Equal Channel Angular Pressing Process Enhanced through Forward Extrusion

The plastic deformation behavior of forward extrusion, equal channel angular pressing, and a combination of the forward extrusion and equal channel angular pressing processes are analyzed by the finite element method. Simulations were carried out under realistic conditions by considering the strain hardening of the material and the degree of friction. Strain homogeneity in the combined processes is also compared to that of the individual forward extrusion and equal channel angular pressing processes. The plastic flow is more complicated and the strain induced is non-uniform in the combined processes. However, the combined processes show no corner gap formation. Moreover, it led to the development of higher strains in a single step compared to the individual processes. In addition, the load requirements for the combined processes are higher than the summation of loads of the individual processes. [doi:10.2320/matertrans.M2009407]X1157sciescopu