Characterization of AlCoCrFeMg High-Entropy Alloy Synthesized Using a Combination of Mechanical Alloying and Hot Pressing

Abstract

Utilizing mechanical alloying and hot compaction, we have successfully made high-entropy alloys (HEAs) with equiatomic proportions of Al, Co, Cr, Fe, and Mg, resulting in alloys demonstrating outstanding mechanical and tribological properties. This study comprehensively explored the impact of variations in phase evolution, density, microstructure, microhardness, and tribological and magnetic effects in the established AlCoCrFeMg HEAs. Field emission scanning electron microscopy (FE-SEM) was employed to examine microstructural changes, complemented by energy-dispersive spectroscopy. The FE-SEM micrographs revealed approximately 1.5% porosity, confirming densification of about 98.8% through Archimedes' principal, and X-ray diffraction identified a body-centered cubic solid solution phase. Furthermore, the melting point of the prepared high-entropy alloy was determined through differential scanning calorimetry. Assessing the mechanical robustness and tribological behavior, a Vickers microhardness tester and a ball-on-disk tribometer were employed for the sintered sample at 950 °C. With an 853.7 ± 20.27 HV_0.5 hardness and a coefficient of friction of 0.49, the developed HEAs exhibited remarkable magnetic properties, as verified by measurements using the physical property measurements system quantum design.