Microstructure and magnetic properties of AlCoCrCuFeNi high-entropy alloy prepared by selective laser melting

Abstract

An equiatomic AlCoCrCuFeNi multi-component high-entropy alloy was prepared by using selective laser melting (SLM) gas-atomized powders, focusing on the effects of different laser volumetric energy densities (VEDs) on the magnetic properties with microstructure evolution. The magnetic, electrical and mechanical properties were studied systematically. The as-printed alloy is mainly composed of body-centered cubic matrix accompanied by the homogeneous precipitation of the Cu-rich face-centered cubic nano-phase. Both alloys display typical ferromagnetism with relatively high coercivity, elevated resistivity, and exceptional hardness. With the VED increased from 54.2 to 109.5 J·mm^-3, the coercivity increased from 218 to 235 Oe, while the saturation magnetization fluctuated within a certain range from 41.1 to 44.1 emu·g^-1. Besides, the printed alloys also have a high nano-hardness and resistivity of 8.7 GPa and 356.9 µΩ·cm, respectively. The higher coercivity and better comprehensive magnetic properties are favorable to design new semi-hard magnetic high-entropy alloys obtained via an SLM method.