Deformation behavior and bonding properties of Cu/Al laminated composite plate by corrugated cold roll bonding

Abstract

Cu/Al corrugated laminated composites were prepared by corrugated cold roll bonding (CCRB), and the deformation behavior and bonding properties of the laminated composites were investigated by experimental research and numerical simulation. The results demonstrate that the “cross shear zones” formed by the CCRB process are substantially more in the Cu layer than the Al layer. Furthermore, increasing the rolling reduction can further expand the difference of the “cross shear zones” between the Cu layer and the Al layer, which is conducive to promote the plastic deformation of the hard-to-deform metal Cu and decreasing the deformation difference between the two metals, thereby reducing the warpage of the Cu/Al laminated composites. It is observed from the microstructure that the rolling reduction increased from 36% to 49%, the morphology of Al adhering to the Cu side at the trough evolves from strip to network shape, even almost covering the entire shear section of the Cu side, and the shear strength increases by 47.44 MPa. Whereas the morphology of Al adhering to the Cu side at the peak is all point-like or flake-like, and the shear strength only increases by 17.74 MPa. Additionally, it is demonstrated that as rolling reduction increases, the shear stress produced by the rapidly expanding “cross shear zones” is the primary cause for the significant increase in bonding strength at the trough. This shear stress accelerates the rupture of the hard brittle layers on the surfaces of Cu layers, while the steadily rising normal stress provides more energy for the bonding between the metals.