Abstract:The simultaneous strengthening of mechanical and magnetic properties is an ideal fabrication strategy for soft-magnetic materials. A non-equiatomic Al₁₉Co₂₀Fe₂₀Ni₄₁ eutectic high-entropy alloy was prepared to investigate the alloying effect of B on the microstructure evolution, phase formation, mechanical and soft-magnetic properties. With the increase in B content, the microstructures of (Al₁₉Co₂₀Fe₂₀Ni₄₁)_100-xB_x alloys transformed from the initial lamellar eutectic structure (x=0) to the divorced eutectic structure (x>0.6). Fine borides precipitated in the intergranular phase (x≥0.6). The hardness of alloys increased from HV 328.66 to HV 436.34 and the compression mechanical performance displayed a transition from plastic material to brittle material. The Al₁₉Co₂₀Fe₂₀Ni₄₁ alloy possesses good soft-magnetic properties, and the minor B addition has little effect on it. Increasing the resistivity can effectively reduce the eddy current loss when used as a soft-magnetic material.

Key words: high-entropy alloy; B element; microstructure; mechanical properties; soft-magnetic properties