Fabrication and investigation of mechanical properties of FGM metal‐based materials with friction stir process and carbon nanotube particles

Abstract

Abstract In this study, Al6061 aluminum sheets and carbon nanotubes with 0, 0.1, 0.5 and 1.5 volume percent were used to produce FGM materials using the friction-stir process and important parameters such as rotational speed, traverse speed and tool angle were investigated for the impact strength and microhardness of the produced composites. The process was carried out at rotational speeds of 950, 1225 and 1500 rpm, traverse speeds of 30, 37.5 and 45 mm/min and angles of 2, 3 and 4 degrees and the mechanical properties and microstructure of the composite material produced were investigated. In order to reduce costs, increase the accuracy of the experimental tests, determine the optimal conditions and also ensure the effectiveness of the parameters for the samples, the response surface design method was applied using Design Expert and Minitab software. In the impact test results, the fracture energy of the manufactured composite material is lower than that of the starting material, and as the rotational speed and tool angle increase, the fracture energy decreases, but as the traverse speed increases, the fracture energy increases. The results of the microhardness test show that the hardness of the produced composites decreases compared to the starting material. As the speed and angle of the tool increases, the hardness decreases, but as the traverse speed increases, the hardness of the composite material increases. The investigation of the effect of the percentage of carbon nanotubes on hardness showed that hardness also increases with increasing percentage of nanotubes.