Unveiling the mechanism for enhanced mechanical–electrical–tribological property integration in CuCrZr/Cu laminated metallic composites via cryorolling and short-term annealing

CuCrZr/Cu/CuCrZr laminated metallic composites (LMCs) were fabricated by hot rolling (HR) followed by cryorolling (CR) and subsequent short-term annealing. The CuCrZr layers accounted for 20.0 vol% of the composite, while the core layer consisted of low-cost pure Cu. The resulting LMCs exhibited enhanced ultimate tensile strength (UTS) and wear resistance relative to the constituent materials. Furthermore, the electrical conductivity of the LMCs was significantly higher than that of the initial CuCrZr (38.3%IACS). After annealing at 673 K for 30 min, the LMCs reached a UTS of 292 MPa, an electrical conductivity of 96.7%IACS, and a wear rate of 2.38 × 10–4 mm3∙N–1∙m–1. These improvements were primarily attributed to optimized precipitation strengthening in the CuCrZr layers and the presence of a high density of annealing twins in the Cu layers. Microstructural characterization revealed uniformly distributed Cr-rich precipitates (≈ 4 nm) in the CuCrZr layer of the CR-A673K sample. Meanwhile, the Cu layer exhibited an annealing-twin area fraction of 43.2% and a 10% increase in the length fraction of Σ3 grain boundaries. This study demonstrates the feasibility of synchronizing CuCrZr aging with Cu recrystallization via CR and short-term annealing, thereby offering a practical design strategy for developing high-performance, low-cost alternatives to pure copper.