A Novel Technique for Development of Aluminum Alloy Matrix/TiB2/Al2O3 Hybrid Surface Nanocomposite by Friction Stir Processing

Compared with non-reinforced aluminum, the aluminum matrix composites reinforced by ceramic phase presents high elastic modulus, high wear resistance, high specific strength, better corrosion resistance at high temperatures and fracture behaviors, which make them as reliable material for aerospace and automotive application. However, their low ductility and softness, which are inherent properties of non-formable reinforcing materials, have limited their applications. Typically, the Material life cycles depend highly on the surface behaviors. Therefore, an optimal situation is to improve the surface layer through reinforcing them by ceramic powders; while the bulk material retains the original compositions with a ductile behavior. In this research work, friction stir processing (FSP) was used to fabricate Aluminum Alloy Matrix/TiB2/Al2O3 hybrid nanocomposites for surface applications. Particles morphology and microstructure characterization was studied by SEM and TEM. Mechanical properties such as tensile test and hardness measurements were carried on surface hybrid nanocomposite and base metal. Micro hardness testing was carried by the use of Vickers hardness measurement method. The improved distributions of nanoparticles were obtained after each FSP pass and progress in mechanical properties was observed.