Microstructure and mechanical properties of Al-Co-Fe-Ni eutectic medium-entropy-alloys

The Al-Co-Fe-Ni eutectic medium-entropy-alloys (EMEAs) were designed to study its microstructure and mechanical properties. It was found that among these medium-entropy alloys, the AlCoFe 1.5 Ni 2.0 alloy has the mixed eutectic structures of CoFeNi-type FCC and AlNi-type B2 while the alloy exhibits excellent compressive strength and ductility at room temperature with a compressive strength super to 2500 MPa and a compression ratio over 46 %, respectively. • Proposed simple mathematical rules to design AlCo a Fe b Ni c EMEAs • Designed precipitate-free Al-Co-Fe-Ni EMEAs with excellent mechanical properties • The excellent properties were attributed to the FCC/B2 structures