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.