| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1468929 | Corrosion Science | 2014 | 8 Pages |
•Ionic liquids were employed in electrochemical pretreatment for AA5083 alloy.•Improved corrosion resistance was observed on the ionic liquid treated AA5083 alloy surface.•The improvement in corrosion was found to be due to an electrochemical etching process similar to acid etching.
Trihexyl(tetradecyl)phosphonium bis(trifluoromethylsulfonyl)amide ([P6,6,6,14][NTf2]) ionic liquid is shown to react with AA5083 aluminium alloy under a two-step anodic polarisation, leading to partial passivation of the surface. Surface characterisation established that an electrochemical etching process had occurred, comparable to acid etching of aluminium. Energy dispersive X-ray spectroscopy (EDXS) and X-ray photoelectron spectroscopy (XPS) results indicated that magnesium de-alloyed from Mg2Si intermetallic particles and metal fluorides were deposited onto the remaining Mg2Si sites, leading to a decrease in the anodic corrosion kinetics (to one third of that of the control) as well as a 100 mV vs. SCE increase in the corrosion and pitting potentials.
