Microstructural Evolution, Performance, and Triboelectric Response of Cu–Fe Composites Processed via Deformation‐Driven Metallurgy

This study investigates the microstructural evolution, mechanical response, tribological performance, and electrical conductivity of Cu–Fe composites fabricated via deformation‐driven metallurgy. Copper powder (99.9%, 250.3 ± 35.6 μm) was reinforced with 2, 4, and 6 wt.% Fe (85.2 ± 12.1 μm, 1 wt.% C) and consolidated through a rapid 10 s severe‐deformation process. Processing led to peak temperatures of 674°C (2 wt.% Fe), 689°C (4 wt.% Fe), and 701°C (6 wt.% Fe), driving dynamic recrystallization and grain coarsening, with average grain sizes of 5.8 ± 1.2, 6.9 ± 1.7, and 8.3 ± 1.3 μm, respectively, compared to 15.1 ± 1.5 μm in unreinforced copper (704°C). Particle dispersion decreased with increasing reinforcement, as indicated by distribution coefficients of 0.88, 0.85, and 0.62. Microhardness peaked at 158.5 ± 3.9 HV for 4 wt.% Fe, but declined to 142.4 ± 4.8 HV at 6 wt.% Fe due to particle clustering and thermal softening. Tensile strength rose from 307.6 ± 8.7 MPa (2 wt.% Fe) to 331.9 ± 9.9 MPa (4 wt.% Fe), before decreasing to 294.7 ± 9.2 MPa (6 wt.% Fe). Ductility decreased from 28.4% ± 1.4% to 19.2% ± 1.5% with increasing Fe, partially recovering to 23.2% ± 1.2% at 6 wt.% Fe due to interfacial debonding. Fractography confirmed ductile dimpled rupture, with strong interfacial bonding at 4 wt.% Fe and debonding at 6 wt.% Fe. Wear resistance was maximized at 4 wt.% Fe, where abrasive wear dominated, while 6 wt.% Fe promoted adhesive wear and accelerated material loss. Electrical conductivity decreased with Fe addition, from 95.1% ± 0.3% IACS (2 wt.%) and 94.3% ± 0.2% IACS (4 wt.%) to 84.3% ± 0.3% IACS (6 wt.%), compared to 96.8% ± 0.3% IACS for unreinforced Cu.