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 110o. 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.