In this paper,a high-entropy alloy Fe34Cr30Mo15Ni15Nb3Al3 was prepared via vacuum induc-tion melting technique.The cast alloy consists of FCC phase,Laves phase and B2-NiAl phase.Then,the high-entropy alloy was subjected to corrosion test at 500℃ in static molten Pb-Bi eutectic(MBE)contain-ing 10-6％oxygen(in mass fraction)for 1000,1500 and 2000 h,respectively.The results showed that af-ter corrosion test,the high entropy alloy did not show obvious signs of being attacked by molten Pb-Bi eu-tectic,namely,there was no obvious dissolution of alloy components and phase transformation,and no obvious inward permeation of Pb and Bi from MBE into the alloy.Only a continuous Fe-Cr spinel scale was formed on the Laves phase region after static corrosion from 1000 h to 2000 h.It is worth mentioning in particular that after exposure for 1000 h,both of Fe-Cr spinel and Cr-depleted Fe-Cr spinel was formed on the surface of FCC/B2-NiAl phase region.As the corrosion time increased to 1500 h,the outer scale of Cr-depleted Fe-Cr spinel formed on the FCC/B2-NiAl phase region spalled off.After exposure for 2000 h,Fe3O4 was generated above the Fe-Cr spinel scale,and covered the entire surface of FCC/B2-Ni-Al phase region.In conclusion,the oxide scales formed on the high-entropy alloy are very thin and com-pact,with a maximum thickness less than 3 μm,so that the high-entropy alloy presented good resistance to MBE corrosion.The outstanding corrosion resistance of high-entropy alloy may be attributed to the ho-mogeneous distribution of Laves phase,which effectively suppresses the outward diffusion of compo-nents of the high-entropy alloy.
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