Surface‐Modified Carbon Fiber Reinforced MC PA6 Composites With Enhanced Mechanical and Tribological Properties

ABSTRACT Monomer‐cast polyamide 6 (MC PA6) is promising for lightweight sliding components but requires improved load‐bearing capacity and wear resistance. Modified carbon fibers (P‐CF) were prepared by acetone desizing, NaOH activation, and PA6 precursor‐derived coating. MC PA6/P‐CF composites with varying filler loadings were fabricated via in situ polymerization. P‐CF promoted heterogeneous nucleation and crystallization and improved thermal stability. At 10 wt% P‐CF, tensile and notched impact strengths peaked, increasing by 18.4% and 27.1%, respectively, relative to neat MC PA6. At 15 wt% P‐CF, the storage modulus increased by 110.4%. The average friction coefficient and specific wear rate decreased by 15.4% and 14.0%, respectively. At matched fiber loadings, P‐CF composites exhibited higher strengths and lower friction coefficients and specific wear rates than composites containing unmodified carbon fibers. Fracture and wear morphologies supported improved fiber‐matrix compatibility associated with the precursor‐derived coating. Fiber load sharing, crack deflection, and constrained matrix deformation contributed to the mechanical and tribological improvements. This strategy provides a viable route to improving the strength and wear resistance of MC PA6.