Tribological performance of induction-sintered aluminum nanocomposites reinforced by electrospun TiO2 ceramic nanofibers via experimental and finite element approaches

: Aluminum matrix composites reinforced with 0, 1, 3, 5, and 10 wt.% electrospun TiO2 ceramic nanofibers (CENF) were fabricated by a powder-metallurgy route using high-frequency induction heat sintering (HFIHS), addressing the limited understanding of how one-dimensional ceramic-nanofiber content governs the combined mechanical, tribological, and sliding-contact behavior of Al composites. This work aims to quantify that composition dependence through combined mechanical, tribological, and finite element (FE) contact-stress characterization of the same material system. Relative density, Vickers hardness, and compressive properties were measured for each composition; dry sliding pin-on-disk wear tests were performed under a 50 N load; and a composition-specific static-structural FE model of the pin-on-disk contact was built using the measured elastic properties and friction coefficient of each composition. Relative density decreased slightly from 99.6% to 98.0% with increasing CENF content, while Vickers hardness increased by up to 32.4%. Compressive yield strength and ultimate compressive strength (UCS) improved with reinforcement, peaking at 415.3 MPa (18% higher than unreinforced Al) at 5 wt.% CENF before declining at 10 wt.% due to nanofiber agglomeration. The 10 wt.% composition exhibited a 76% reduction in specific wear rate and a 38% reduction in coefficient of friction (COF) relative to unreinforced Al. The FE model predicted a 22% reduction in maximum von Mises stress and a 5% reduction in maximum contact pressure with increasing CENF content, with the predicted stress correlating strongly with the prescribed COF (r = 0.997) and moderately with the measured specific wear rate (r = 0.864). These results demonstrate that electrospun TiO2 nanofibers effectively and simultaneously improve the mechanical and tribological performance of powder-metallurgy Al composites, and that a simplified static FE model can meaningfully capture the composition dependence of their sliding-contact behavior.