Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1469618 | Corrosion Science | 2012 | 7 Pages |
Anodizing of Al–Ti alloys, containing 3, 12, 15, 30 and 45 at.%Ti, is examined at 5 mA cm−2 in 1 mol dm−3 sulphuric acid at 293 K. Porous films are formed up to 15 at.%Ti, with titanium increasing the anodizing voltage and pore size. In contrast, a barrier-type film is formed at 30 at.%Ti, with a finely porous outer region, while at 45 at.%Ti, barrier-type film growth is accompanied by oxygen generation. Ti:Al atomic ratios in the films are similar to those in the respective alloys. Reduced levels of sulphur occur in barrier-type films compared with porous films.
► Porous anodic films are formed on Al–Ti alloys in sulphuric acid up to ∼20 at.%Ti. ► Atomic ratios of Al to Ti are similar in films and alloys. ► Incorporation of Ti4+ ions into anodic alumina increases the pore size. ► Films formed on Al–30 at.%Ti and Al–45 at.%Ti are largely barrier-type. ► Barrier-type films contain significantly less sulphur than the porous films.