Element-resolved electrochemical analysis of transpassive dissolution and repassivation behavior of the multi-principal element alloy AlTiVCr

Potential Dependent Mn Oxidation and Its Role in Passivation of Ni38Fe20Cr22Mn10Co10Multi-Principal Element Alloy Using Multi-Element Resolved Atomic Emission Spectroelectrochemistry

“…This technique is useful, in particular, for the selective dissolution in multi-phase alloys 40 and passivation of Ni-based alloys [22]. [41][42][43][44] It was recently deployed to examine a nearly equiatomic Al-Ti-V-Cr MPEA in Cl --containing media, 45,46 equiatomic Co-Cr-Fe-Mn-Ni in 0.1 M H 2 SO 4 , 25 and non-equiatomic Ni-Cr-Fe-Ru-Mo-W in 2 M H 2 SO 4 . 47 In combination with ex situ XPS surface characterization of the outer layers of oxidized surfaces, AESEC provides a powerful approach to understand the fate of each alloying element.…”

Recent insights in corrosion science from atomic spectroelectrochemistry

“…Moreover, the presence of Ti was seen to inhibit the transpassive dissolution potential of V and Cr. [ 88 ] Similarly, Ru addition was found to improve the Cr‐based passivity of non‐equiatomic NiCrFeRuMoW alloy in H 2 SO 4 . [ 89 ] Although, being considered as ‘expected’ that additional passive element improves the passivity, the mechanistic understanding of the evolution of passive film morphology in such cases is limited.…”

“…Apart from conventional alloys, most multi‐principal element alloys studied using ASEC are found to dissolve incongruently. [ 85–91 ] Evolution of dissolution rate of each alloying element from alloys is found to depend on applied potential, exposure duration, pH, and so on. For example, both pH and exposure duration influenced the dissolution ratios of $$\frac{{{{{\upsilon}}_{Zn}}}}{{{{{\upsilon}}_{Al}}}}$$ in Al‐Zn alloys, [ 72 ] $$\frac{{{{{\upsilon}}_{Mg}}}}{{{{{\upsilon}}_{Si}}}}$$ in Mg 2 Si.…”

“…Apart from conventional alloys, most multi-principal element alloys studied using ASEC are found to dissolve incongruently. [85][86][87][88][89][90][91] Evolution of dissolution rate of each alloying element from alloys is found to depend on applied potential, exposure duration, pH, and so on. For example, both pH and exposure duration influenced the dissolution ratios of…”

“…A few passive MPEAs are found to dissolve significantly in the OER region during anodic polarisation. [87][88][89] In such cases, dissolution behavior was incongruent, suggesting dissimilar responses of different oxides (present in the surface film of alloys) to oxygen evolution. In contrast to the systems mentioned above, the dissolution rate of Ti slightly decrease and remained independent of applied anodic potential during oxygen evolution in 0.1 M H 2 SO 4 .…”