Investigation of Microstructure and Mechanical Properties in Hybrid Composites Produced with Fe3O4/nanographene Additives to Al7020 Alloy by Powder Metallurgy Method via Mechanical Alloying

The objective of this work is to enhance the microstructural and mechanical characteristics of Aluminium (Al) 7020 alloys, which are receiving growing application in the aerospace sector. The mechanical properties of Al 7XXX series alloys are at high levels compared to other Al alloys. However, the need for Metal Matrix Composites (MMC) is increasing day by day to increase the mechanical properties to the desired levels. Powder metallurgy is one of the advanced production techniques for MCCs. It is known that microstructural and mechanical properties are improved by mechanically alloying (MA) and homogeneous mixing of powders in the structure. Investigated were the effects of various mechanical alloying durations (1, 2, 4, and 8 hours) on the mechanical and microstructural characteristics of composites formed by reinforcing nanographene at 0.25% with 10% Fe3O4 fixed in Al7020 alloy. Density, XRD and SEM analyses were performed on all composite samples for characterization purposes. After that, the mechanical characteristics of the hybrid composite samples were determined by accurate hardness and tensile testing methods. The sample who received mechanical alloying for 8 hours achieved the highest tensile strength of 335 MPa.