An electrochemical study of repassivation of aluminium alloys with SEM examination of the pit interiors using resin replicas

Potentiodynamic study of Al–Mg alloy with superhydrophobic coating in photobiologically active/not active natural seawater

“…E ptp does not depend on the initial surface state condition, rather on the alloy bulk in a given corrosive environment [24]. In accordance, we found a relatively stable E ptp , E ptp =24226 (sd) mV vs. Zn [29,45]. The simultaneous E ptp appearance, i ptp decrease and E ptp -E prot enhancement with time agrees with the presence of an organic layer adsorbed at the metal surface.…”

Inflection of backward sweep of cyclic polarization curve: Pit transition potential Eptp

“…Both Pride et al and Zhang and Frankel attributed this phenomenon to surface acidification. However, Moore et al challenged surface acidification theory by comparing the back scan of the stirred test with that of the stagnant solution. They found that although the current in the back scan for the stirred test was reduced, but still much larger than the passive current in the forward scan, suggesting that the transition was not entirely caused by surface acidification.…”

“…The findings confirmed Newman's theoretical analysis: “tunneling is not necessarily some exotic property of {100} planes, but may simply represent the efficient use of a current that would be too low to sustain the right local chemistry.” According to Newman et al, it was predicted that an “array of tunnels” would form, but in Moore's work only isolated tunnels were found. Additionally, the inflection might be indistinguishable if the number of tunnels is not enough but the fact is, the reported E ptp in Moore et al is marked as pitting potential. Therefore, there is still improvement room for this pit‐tunneling switch theory.…”

“…Moore et al investigated this inflection of AA 5083 and spray formed Al–Mg–Li alloy by examining SEM of pit interiors using resin replicas. They found one‐dimensional tunnels formed after transition but tunnels absent for the forward sweep, thus proposed that the transition was caused by the switch from pit growth to one‐dimensional tunneling.…”

Mg Alloy Surface Treatment

“…This process is called selfalignment of the information on the magnetic alignment of PAA. During the forming of PAA in the anodizing process, self-alignment, voltage, and the type of electrolyte are known to be affected by the temperature of the electrolyte [22,23]. In the case of the anodizing voltage expressions (2) and (3) and it is known that as determining the distance between the pore size of the PAA and the pores with the pore, where D-pore, Dint, D-cell the size of each pore, the pore , denotes the size of the cells, U is Empty indicate the anodizing voltage: Figure 5.…”