Designing Eutectic High‐Entropy Alloys Containing Nonmetallic Elements

Eutectic high‐entropy alloys (EHEAs), as an important branch of high‐entropy alloys (HEAs), have become hotpots in the materials field due to the excellent combination of mechanical properties and casting liquidity. However, designing of EHEAs containing nonmetallic elements has been rarely reported. Herein, a new strategy to design EHEAs containing nonmetallic elements by introducing an idealized mode of A‐(M + N) and using computer‐aided thermodynamic calculations is proposed. Based on this strategy, four new EHEAs, namely, CoFeNi 2 –Ti 0.48 Si 0.8 , CoCrNi 2 –V 0.86 B 0.43 , CoCrFeNi 2 –V 0.89 B 0.45 Si 0.15 , and CoCrNi 2 –MoC 0.6 , are designed and prepared. The CoFeNi 2 –Ti 0.48 Si 0.8 and CoCrNi 2 –MoC 0.6 EHEAs are composed of face‐centered‐cubic (FCC) + M 16 Ti 6 Si 7 ‐type silicide and FCC + M 23 C 6 + M 6 C‐type carbide, respectively. The CoCrNi 2 ‐V 0.86 B 0.43 and CoCrFeNi 2 ‐V 0.89 B 0.45 Si 0.15 EHEAs exhibit the same eutectic microstructure as FCC + M 3 B 2 ‐type boride. The synthesized EHEAs containing nonmetallic elements show excellent mechanical properties. The experimental result indicates that this strategy can provide a feasible and effective way to develop new EHEAs with nonmetallic elements.