Microstructure and mechanical properties of AlCuNiFeCr high entropy alloy coatings by mechanical alloying

AlCuNiFeCr high entropy alloy (HEA) has become a novel and very promising material in recent years due to their excellent mechanical properties. However, only a few papers discussed on coating of AlCuNiFeCr high entropy alloy by a powder metallurgy route. In the present work, non-equiatomic AlCuNiFeCr HEAs were coated on stainless steels by mechanical alloying with different ball to powder ratio (BPR). The effects of alloying elements, different BPRs and annealing treatment on characteristics of the HEA coatings were studied. The results show that the AlCuNiFeCr coatings were successfully synthesized by mechanical alloying technique, a homogeneous microstructure and improved mechanical properties of the coating layers were obtained at a higher BPR after a long milling duration. The large amounts of FCC solid solution phase and (Al,Cr) oxide particles was formed after annealing at the HEA coatings.