Microstructure and corrosion properties of AlCrFe2Ni2Bx (x = 0, 0.04, 0.1, 0.2) high entropy alloy

This study examined how varying B element concentrations (x = 0, 0.04, 0.1, and 0.2 at.%) affect the microstructure, corrosion resistance, and characteristics of passive films in AlCrFe₂Ni₂B_x high-entropy alloys. The findings indicated that as-cast AlCrFe₂Ni₂B_x alloys transitioned from distinct grain structures to dendritic structures. Increased B content significantly enhanced inter-dendritic regions, resulting in notable grain refinement during this transition. In a 3.5 wt.% NaCl solution, B content increase from 0 at.% to 0.1 at.% improved corrosion resistance, while a 0.2 at.% concentration slightly reduced resistance. These effects stemmed from microstructural changes and variations in passive film composition.