Integrated microstructural thermo mechanical and tribological evaluation of copper matrix composites reinforced with coated short carbon fibers

Abstract This study presents the sustainable fabrication and comprehensive evaluation of copper-matrix composites reinforced with short carbon fibers (SCFs) at different ratios (0–5 wt%). The composites were produced using powder metallurgy and hot-pressing methods, with electroless nano-copper coating applied to SCF, graphite (C), and molybdenum disulfide (MoS₂) to improve interfacial bonding. X-ray diffraction (XRD) and scanning electron microscopy (SEM) confirmed the structural integrity and uniform distribution of SCF, supported by quantitative heat map analysis and volume fraction estimation. A systematic investigation showed that increasing SCF content led to a controlled decrease in density, electrical conductivity, and thermal conductivity—as expected due to the reinforcement—while significantly increasing microhardness by 28% and boosting thermal dimensional stability. The coefficient of thermal expansion decreased notably at higher temperatures. Wear resistance also improved, with notable reductions in both specific wear rate and coefficient of friction under various loads. Abbott–Firestone curve analysis further demonstrated optimal surface integrity at 2–3 wt% SCF and the highest load-bearing capacity at 5 wt%. These findings indicate that optimized SCF reinforcement significantly enhances the thermal, mechanical, and tribological properties of copper composites, offering a promising route toward high-performance, lightweight materials for demanding engineering applications.