An experiment study was conducted to locally improve the properties of Al6082-T6 alloy by adding hard particles reinforcement using Friction Stir Processing. Aluminum and its alloys are the most used as a substrate material in the fabrication of Aluminum surface composites because of their lightweight. Thus, aluminum alloy is widely preferred in generating surface composite that is used in sports, marine, aerospace, aircraft, automobile, electronics, railway, etc. Industry requirements ask for good-cost materials with very high properties and light weight. To meet the market requirements, this study has been conducted to investigate the development of the microhardness of Aluminum matrix composites after treating by Friction Stir Processing. From an economic perspective, it is important to enhance the property of the materials by treating the surface instead of the core of the materials. Thus, FSP consid ered in this study as a one of the green fabrication process because it can be done without fume or toxic gases during processing.

The basic principle of the Friction Stir Process is to use a rotating tool that provides the friction between the tool and the workpiece material producing heating, to produce the wanted plastic deformation. This project aimed to fabricate composites with different reinforcements. The reinforcements used were diamond, cubic Boron Nitride and Graphene. Friction Stir Process was carried out at the tool rotating speed of 1000, 1200 and 1500 rpm and traversing speed of 2, 3 and 5 mm/s. Effects of the number of Friction Stir Process passes were investigated. The samples were all mounted, ground, polished, and analyzed by SEM and optical microscope devices. Microhardness was recorded across the Friction Stir Process region using DU-RAMIN-40 AC1 device with applied load 20, 50, 100 gf.

It was concluded that a good refinement of the particles size can be achieved in the processed zones for all types of reinforcement. Increasing the number of stirring passes produced well distribution of reinforcement particles and reduced the agglomeration. While increasing rotation speed during processing of graphene reinforcement led to generate more heat, subsequence more agglomeration would be produced. Finally, the results showed that by incorporating diamond reinforcement using single FSP-pass increase the microhardness by about 20% while using double FSP-pass it was found that there was no significant improvement in the microhardness of the composite. A good improvement was also achieved by incorporating the cBN reinforcement where the improvement in the microhardness was also about 20% using single FSP-pass. Increasing rotating speed in FSPed GNP reinforcement leads to generate more heat which leads to more agglomeration or clustering of the reinforcement particles