The effects of residual stress on the tensile behaviors of Cu/Nb laminated metal composites

The coupling between residual stress and heterogeneous interfaces complicates the understanding of the specific role of residual stress in tensile behavior. Here, we constructed an ideal system of Cu/Nb laminated composites featuring nearly identical microstructures but distinct residual stress. Results show that higher residual stress gives slightly superior strength. This arises from premature yielding in Cu layers coupled with delayed yielding in Nb layers, extending the elastic-plastic stage and promoting dislocation accumulation. This effect, however, rapidly diminishes during plastic deformation. Thus, while residual stress can initially modulate local yielding sequences, the macroscopic tensile behaviors remain governed by intrinsic microstructure.