Development characterization and machinability study of high entropy alloy reinforced aluminium metal matrix composite

This work describes the successful development of a unique Al-MMC using the stir casting technique. The base matrix is Al 6063 alloy, and the reinforcement is 3% HEA powder, which contains Fe, Cr, Mn, Al, and Ni. HEA was chosen as the reinforcing phase because of its remarkable combination of high strength, wear resistance, corrosion resistance, and thermal stability-all of which can greatly improve the performance of traditional aluminium alloys. The EDS, AFM, Gleeble-TMS, SEM, and XRD were used to comprehensively examine the produced composite to evaluate its phase composition, grain morphology, and microstructural refinement. The homogeneous dispersion and strong interfacial bonding of HEA particles within the Al 6063 matrix are responsible for the significant strength gain observed in mechanical testing, particularly tensile strength evaluation, when compared to the base material. Twenty-seven milling experiments were conducted using a controlled experimental design to examine machinability. The input parameters were spindle speed, feed rate, and depth of cut, and the responses were measured as MRR and R_a. Under various criteria weighting scenarios, multi-criteria MCDM techniques-MARCOS, CoCoSo, and MABAC were used to produce consistent rankings of the milling conditions. Experiment 9, with a spindle speed of 170 rpm, feed rate of 41 mm/rev, and depth of cut of 0.8 mm, emerged as the most valuable compromise between high MRR and low R_a. The results demonstrate that adding HEA reinforcement improves the composite's tensile strength, microstructural integrity, and machinability. This makes the material promising for demanding engineering applications in precision tooling, biomedical implants, and aerospace components where high strength, wear resistance, and surface finish are essential.