To address tribological degradation of mechanical components under elevated temperatures, this study fabricates Ni 3Al-based composite coatings with SiO 2 additions (0–20 wt%) on carbon steel substrates through ultrasonic vibration-assisted laser cladding. The synergistic effect of SiO 2 on microstructural evolution and elevated-temperature wear resistance is systematically elucidated. The analytical characterization indicates that the silica liquid phase formed during the processing can effectively fill the pores. Acting as heterogeneous nucleation sites, SiO 2 particles refine grain structure (average 2.1 μm reduction) and mitigate elemental segregation, enhancing coating densification. The optimized 15 wt% SiO 2 coating demonstrates superior tribological performance, exhibiting 32.4 % and 25.6 % reductions in friction coefficient (0.28 → 0.19) and specific wear rate (3.7 × 10 −5 → 2.75 × 10 −5 mm 3/N·m), respectively. This performance improvement stems from the dense oxide film (alumina/copper oxide nanocomposite) formed in situ by silica during the friction oxidation process, which effectively lubricates the wear interface under thermomechanical coupling conditions.