Interface-position-dependent structure evolution and mechanical behavior of corrugated cold rolled Cu/Al clad plate: experiment and simulation

Abstract

Abstract Cu/Al corrugated clad plates were prepared by the novel corrugated cold roll bonding (CCRB) process to investigate the stress states, microstructures and mechanical behaviors of the corrugated clad plate adjacent to various corrugated interface positions by experimental and numerical simulation methods. The results show that the CCRB process induces multiple “cross shear” zones in the rolling deformation zone. This greatly accelerates the plastic deformation of Cu layer and significantly diminishes the deformation difference between Cu and Al dissimilar metals with a result of the reduced warpage amplitude. Also, the microstructure at different positions is obviously different due to the various stress states and deformations. Especially at positions III (trough) and IV (front waist), the elongated grains and fine equiaxed grains are formed under the severe plastic deformation and the shear stress. And the ultimate tensile strength achieves a maximum value of 209.25 MPa at position III (trough), and does the minimum value of 182.43 MPa at position II (back waist). The strength of the Cu/Al corrugated clad plate is affected by both the dislocation strengthening and grain boundary strengthening. When the plastic deformation is severe, the dislocation strengthening mechanism is dominant in Cu matrix, while the fine-grain strengthening mechanism in Al matrix.