Structure and properties of AlCoFeCuMox high entropy alloy coatings prepared by laser cladding and applications on drones for aerospace innovation competitions

In response to the growing demands for lightweight design and enhanced surface performance in aerospace innovation competitions, this study aims to improve the surface properties of aluminum alloys – widely used in drone fabrication due to their low density – by developing AlCoFeCuMox high entropy alloy (HEA) coatings via laser cladding technology. Systematic characterization using scanning electron microscopy (SEM), X-ray diffraction (XRD), and energy dispersive spectroscopy (EDS) revealed a remarkable microstructural architecture: the coating exhibits a dense and homogeneous morphology with stable phase constituents face-centered cubic (FCC) + body-centered cubic (BCC) solid solutions and well-dispersed elemental distribution, featuring controlled segregation of Mo at interdendritic regions. This unique composition facilitated exceptional mechanical and corrosion resistance. Notably, the coating achieved a hardness range of 440–470 HV, surpassing that of traditional aluminum alloys, and demonstrated low wear rates of 2.1×10 -5 to 2.9×10 -5 mm 3 /(N·m), indicative of robust tribological performance. Electrochemical testing in a 3.5% NaCl solution further confirmed its corrosion resilience, with self-corrosion potentials spanning -1.07 to -1.00 V and self-corrosion current densities ranging from 2.06×10 -4 to 7.38×10 -4 mA/cm 2 . The passivation layer effectively inhibited Cl - penetration, endowing the coatings with exceptional resistance to pitting corrosion. Collectively, these findings establish the AlCoFeCuMox HEA coating as a promising candidate for aerospace applications, offering a synergistic balance of lightweight, high hardness, wear resistance, and corrosion protection essential for competitive drone systems.