Microstructure, thermal properties, and corrosion behaviors of FeSiBAINi alloy fabricated by mechanical alloying and spark plasma sintering

An equiatomic FeSiBAlNi amorphous high-entropy alloy （HEA） was fabricated by mechanical alloying （MA）. A fully amorphous phase was obtained in the FeSiBAlNi HEA after 240 h of MA. The bulk FeSiBAlNi samples were sintered by spark plasma sintering （SPS） at 520 and 1080℃ under a pressure of 80 MPa. The sample sintered at 520℃ exhibited an amorphous composite structure comprising solid-solution phases （body-centered cubic （bcc） and face-centered cubic （fee） phases）. When the as-milled amorphous HEA was consoli- dated at 1080℃, another fcc phase appeared and the amorphous phase disappeared. The sample sintered by SPS at 1080℃ exhibited a slightly higher melting temperature compared with those of the as-milled alloy and the bulk sample sintered at 520℃. The corrosion behav- iors of the as-sintered samples were investigated by potentiodynamic polarization measurements and immersion tests in seawater solution. The results showed that the HEA obtained by SPS at 1080℃ exhibited better corrosion resistance than that obtained by SPS at 520℃.