Fabricating antibacterial CoCrCuFeNi high-entropy alloy via selective laser melting and in-situ alloying

A quasi-equiatomic CoCrFeCuNi high-entropy alloy (HEA) with a broad-spectrum antibacterial ability and good mechanical properties has been fabricated by selective laser melting (SLM) and in-situ alloying of a blend of pre-alloyed CoCrFeNi powder and Cu elemental powder. The as-built HEA alloy has a homogeneous distribution of Cu and presents a single FCC phase. Compared with the same HEA fabricated using the traditional ingot metallurgy (IM) process, the HEA alloy fabricated by SLM releases more Cu ions to prevent growth and biofilm formation by gram-negative Escherichia coli and gram-positive Staphylococcus aureus, which enhances the applicability of the HEA alloy in potential applications that requires antibacterial ability. The results of this study confirm the feasibility of combining the antibacterial CoCrFeCuNi HEA alloy and SLM technology in fabricating complex shaped parts or structures with a strong antibacterial ability to be used in medical application or other environments desired for antibacterial ability.