Effect of rolling reduction on the microstructure of the copper/aluminum composite strip produced by micro flexible rolling

Abstract

Copper/aluminum (Cu/Al) laminated composite has been extensively applied in the fields of batteries, electronics and electrochemistry owing to its cost reduction, light weight, good conductivity and resistance to corrosion. The Cu/Al composite strips produced by micro flexible rolling consist of three regions based on different thickness, i.e. the thicker, the transition and the thinner zones, and have a broad application prospect, especially in micro-electromechanical systems (MEMS). In this study, the effect of rolling reduction on the coordinated deformation of the Cu/Al interface and the microstructure of Cu/Al matrixes at three regions were investigated. The microstructure of the specimens was characterized using scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and the thickness of thin strips with varying thickness (TSVT) were measured by laser scanning microscope to explore the mechanism of microstructural evolution. The results show that the increase of rolling reduction gives a rise to the proportion of deformation occurred in the Al matrix, and the fracture of the intermetallic compounds (IMCs) is observed at the interface, which plays a significant role of transmitting and releasing stress during plastic deformation.