Hybrid metal matrix composites (HMMCs) are designed with the increased demand of light weight, strong and wear resistant materials in automotive and aerospace industry and structural fields. This paper reports the preparation and full characterization of Al2011-based HMMCs reinforced by different weight percent (2-10 wt%) of nano Titanium Carbide (TiC), and of a fixed composition of 4 wt% of nano Molybdenum Disulfide (MoS2) prepared by stir casting. Nano TiC with its mechanical strength and boost in load-carrying strength was added, and MoS2 was added as a solid lubricant to improve the tribology properties. During development, appropriate preprocessing, as well as drying and preheating of powder, led to an equal distribution of reinforcement and wettability. SEM, EDS and XRD microstructural studies affirmed homogeneous dispersion and integrity at interfaces. Density and porosity studies have shown very little defect in casting and the maximum densification was found at 8 wt% TiC. The tensile strength, hardness and impact resistance were significantly improved by mechanical testing and reached the maximum at 8 wt% TiC where agglomeration of particles decreased performance slightly. The dry sliding tribological tests showed exceptional decreases in wear speed, wear loss, and coefficient of friction with rising reinforcement level especially the synergistic impact of surface hardening TiC and lubricant MoS2. Surface morphology due to wear indicated a shift in wear mechanisms to an oxidative and mild abrasive wear regime in composites compared with adhesive and abrasive wearing of the base alloy. The 8 wt% TiC + 4 wt% MoS2 hybrid composites provided the most favorable mechanical and tribological performance. Although TiC/MoS2 hybrids have been used in other Al matrices (e.g., AA6061/AA7075), there is still limited report on systematic optimization in the Al2011 matrix; this work fills this gap by bridging process controls with a complete microstructural-mechanical-tribological analysis.
