Work

Investigation on the microstructure evolution and strengthening behavior of rolled bonding Cu strip

Year: 2024

Type: article

Abstract: In this paper, φ57µm pure copper wire is machined into copper strips with different thickness by rolling processing, and its strengthening behavior and microstructure evolution were studied. The results show that the uneven deformation behavior of rolled copper strip is divided into three deformation zones; With the increase of reduction rate, the strength of copper strip increases rapidly at first and then slowly; The main contribution to the strength improvement is the interaction of dislocation, grain boundary and texture; When the thickness of copper strip is 11.4 µm, the average grain size decreases to 0.343 µm, while the strength reaches 327 MPa. The dislocation density can not form large-scale entanglement accumulation due to the thinning of copper strip thickness and severe grain refinement; The grain orientation appear periodic cycle transition between <110> and <111> <001> as the sample thickness decreases; The grains in the fracture area of the copper strip are elongated and refined during stretching, and flow towards the centerline of the cross-section. The fracture morphology presents a symmetric and regular "wedge shape" at the reduction rate range of 35% - 50%. The irregularity degree of fracture morphology is deepened when the reduction rate is within 60% - 80%, and the angle of fracture surface deviating from TD direction also increases gradually, and the strengthening of copper strip approached the limit.

Source: Journal of Science Advanced Materials and Devices

DOI: 10.1016/j.jsamd.2024.100835