Constrained groove pressing process of Al/Cu bimetal sheet

Constrained groove pressing (CGP) process is a severe plastic deformation (SPD) method to reach to good mechanical and metallurgical properties in sheet metals. In this study, semi-CGP process was performed on the Al/Cu bimetal sheet to investigate the variations in its mechanical and metallurgical properties. The sheet was annealed, and then the CGP-processed. The sheet was fractured after applying two passes (eight steps). Also for studying the strain distribution, the process was simulated using the finite element (FE) method and verified by the experimental test. Results showed that the CGP process increased the yield stress and ultimate tensile strength of the bimetal sheet while reducing its ductility. Grain size was reduced in both Al and Cu layers, and reduction rate in the single-passed sample was greater than the double-passed one. Fracture mode before and after the process was ductile in both layers. FE results indicated that the strain imposed on the Cu layer was lower than the Al layer in all steps.