Anodic dissolution and protection of aluminum alloy 7075 in hydroxide solutions

Journal Article · Sat Mar 01 04:00:00 EST 1997 · Corrosion

DOI:https://doi.org/10.5006/1.3280458· OSTI ID:458216

McCafferty, E; Trzaskoma-Paulette, P ^[1]

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1. Naval Research Lab., Washington, DC (United States)

Dissolution of Al 7075 (UNS A97075) in sodium hydroxide (NaOH) solutions results in formation of a black, loosely adherent film of corrosion products that provides partial protection in the aqueous environment. Optical and scanning microscopy showed the reaction product film is a bilayer, with a thin, adherent inner layer and a thicker, more fragile outer layer. The reaction mechanism involves the dissolution of aluminum followed by formation of a precipitated film. Corrosion protection at moderate hydroxide concentrations is provided by the use of a partially fluorinated amino-surfactant or a silicon nitride (Si{sub 3}N{sub 4}) coating prepared by ion beam-assisted deposition.

• Sponsoring Organization: USDOE
• OSTI ID: 458216
• Journal Information: Corrosion, Journal Name: Corrosion Journal Issue: 3 Vol. 53; ISSN 0010-9312; ISSN CORRAK
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM BASE ALLOYS
CORROSION
CORROSION PRODUCTS
CORROSION PROTECTION
DISSOLUTION
FILMS
ION BEAMS
PROTECTIVE COATINGS
SILICON NITRIDES
SODIUM HYDROXIDES