| Abstract Scope |
Carbon–metal composites (CMCs) have emerged as promising candidates for next-generation, high-efficiency electrical conductors in power transmission and energy-delivery systems. Although hot extrusion has shown considerable potential for improving the bulk electrical performance of these materials, the relationships among extrusion parameters, die geometry, material flow, microstructural evolution, carbon dispersion, and electrical transport remain insufficiently understood. In particular, the combined effects of extrusion temperature, ram speed, extrusion ratio, and die design have not been systematically investigated, limiting the development of processing strategies that reliably maximize conductor performance. This work systematically investigates the effects of hot-extrusion processing parameters and die geometry on the microstructural evolution and electrical performance of carbon-reinforced aluminum composites developed for power-transmission conductors. DEFORM finite element simulations, combined with experimental extrusion trials, are used to investigate material flow, flow stresses, flow nets, and deformation behavior as influenced by die geometry. In addition, optical and polarized-light microscopy and electrical conductivity measurements are employed to correlate carbon distribution and interfacial evolution with composite performance. |