Wear and tribological analysis of graphite-reinforced Al6061-TiB2 hybrid composites fabricated by stir casting

Abstract This study investigates the Al6061-TiB2-Gr hybrid composites developed by high-energy stir casting with varying TiB2 (5, 10, 15, and 20 wt.%) and fixed graphite (2 wt.%). The research focuses on both chemical and tribological characterization. The phase composition and elemental analysis were examined using SEM and EDS, confirming uniform distribution and strong bonding of reinforcements. Wear tests were conducted using a pin-on-disc setup under different loads (5–15 N) and sliding distances (1000–3000 m). The response surface methodology (RSM) and ANOVA were employed to model the effects of reinforcement content, load, and sliding distance on wear rate and friction coefficient. The Al6061-20TiB2-2Gr composite exhibited a 68% reduction in wear rate and 71% lower friction compared with the base alloy. The combination of hard TiB2 and self-lubricating graphite enhanced surface protection, resulting in smoother wear morphology. The study confirms that the optimized hybrid composite provides superior tribological performance and chemical stability, suitable for eco-efficient engineering applications.