Equal channel angular pressing (ECAP) is one of the most prominent severe plastic deformation (SPD) processes to achieve ultra-fine grained (UFG) structures. Using bimetallic specimens has been recently considered in this process. In the present study, the effects of casingwith lower strength, compared to the billet, and the casing thickness on mechanical properties of ECAPed billet are investigated experimentally and by simulation. Bimetallic specimens of pure Cu and Al-7075 alloy with different dimensions are ECAPed in one pass at room temperature. The effect of casing and its thickness on the required forming load, the average amount of equivalent plastic strain and Vickers micro-hardness, and their distributions in cross section of billet, strain homogeneity, compression strength of billets, and stress distribution in the deformation zone are investigated.

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