Lithium-aluminum-carbonate-hydroxide hydrate coatings on aluminum alloys: Composition, structure, and processing bath chemistry

Journal Article · Sat Jun 01 04:00:00 EDT 1996 · Journal of Materials Research

DOI:https://doi.org/10.1557/JMR.1996.0188· OSTI ID:285868

Drewien, C A; Eatough, M O; Tallant, D R; Hills, C R; Buchheit, R G ^[1]

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1. Materials and Process Sciences Center, Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)

A new corrosion resistant coating, being designed for possible replacement of chromate conversion coatings on aluminum alloys, was investigated for composition, structure, and solubility using a variety of techniques. The stoichiometry of the material, prepared by immersion of 1100 Al alloy into a lithium carbonate-lithium hydroxide solution, was approximately Li{sub 2}Al{sub 4}CO{sub 3}(OH){sub 12}{center_dot}3H{sub 2}O. Processing time was shown to be dependent upon the bath pH, and consistent coating formation required supersaturation of the coating bath with aluminum. The exact crystal structure of this hydrotalcite material, hexagonal or monoclinic, was not determined. It was shown that both the bulk material and coatings with the same nominal composition and crystal structure could be formed by precipitation from an aluminum supersatured solution of lithium carbonate. {copyright} {ital 1996 Materials Research Society.}

• Research Organization: Sandia National Laboratory
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 285868
• Journal Information: Journal of Materials Research, Journal Name: Journal of Materials Research Journal Issue: 6 Vol. 11; ISSN JMREEE; ISSN 0884-2914
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
ALUMINIUM COMPOUNDS
CHEMICAL COMPOSITION
CORROSION PROTECTION
CRYSTAL STRUCTURE
HYDRATES
HYDROXIDES
LITHIUM CARBONATES
MICROSTRUCTURE
PRECIPITATION
SOLUBILITY
SURFACE COATING