Production of Lightweight Metals Containing High-Entropy Alloys via SHS Process

In this study, the lightweight metals containing high-entropy alloys (L-HEA) having the targeted composition as the equiatomic AlSiTiME1ME2, non-equiatomic Al3.5Si2.0Ti1.0Cu1.5Ni2.0, and Al2.0Ti1.5V3.5Fe2.0Cr1.0 were produced by a self-propagating high-temperature synthesis (SHS). The SHS process, known for its rapid and energy-efficient nature, was chosen to meet the increasing demands for new materials in the world of alloys. ME1 and ME2 were selected from Nb, Mg, V, Cr, and Mn. The metallic Al, Si, and Mg were used as the reducing agent and metal sources for the targeted compositions, while metal oxide powders were chosen for the transition elements sources. The effects of the targeted compositions on the microstructure and mechanical properties in L-HEAs were investigated. The micro-Vickers hardness test, scanning electronmicroscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray fluorescence (XRF), and X-ray diffraction (XRD) analyses were performed for the characterization of the SHS product. The highest metal recovery was calculated as 89.4% for Al3.5Si2.0Ti1.0Cu1.5Ni2.0 production. The obtained L-HEAs exhibit very high micro-Vickers hardness of up to 942.6HV. The L-HEA having Al2.39Ti0.62V3.68Fe2.25Cr1.07 composition has a simpler and homogenous microstructure.