Accession Number : ADA305210

Title :   Galvanic Coupling Between D6AC Steel, 6061-T6 Aluminum, Incone1 718, and Graphite- Epoxy Composite Material: Corrosion Occurrence and Prevention.

Descriptive Note : Technical paper,

Corporate Author : NATIONAL AERONAUTICS AND SPACE ADMINISTRATION HUNTSVILLE AL GEORGE C MARSHALL SPACE FLIGHT CENTER

Personal Author(s) : Danford, Merlin D. ; Higgins, Ralph H.

PDF Url : ADA305210

Report Date : DEC 1983

Pagination or Media Count : 18

Abstract : The effects of galvanic coupling between D6AC steel, 6061-T6 aluminum, Inconel 718, and Graphite-Epoxy Composite Material (G/E) in 3.5% NaCl have been studied. Measurements of corrosion potentials, galvanic currents and corrosion rates of the bare metals using weight-loss methods have served to establish the need for corrosion protection in cases where D6AC steel and 6061-T6 aluminum are galvanically coupled to G/E in salt water while Inconel 718 was shown to be compatible with G/E. Six tests were made to study corrosion protective methods for eliminating galvanic corrosion in the cases of D6AC steel and 6061-T6 aluminum coupled to G/E. These results indicate that, when the G/E is completely coated with paint or a paint/polyurethane resin combination, satisfactory protection of the D6AC steel is achieved with either a coat of zinc-rich primer or a primer/topcoat combination. Likewise, satisfactory corrosion protection of the aluminum is achieved by coating it with an epoxy coating system. jg p18

Descriptors :   *COUPLING(INTERACTION), *ALUMINUM ALLOYS, *CORROSION INHIBITION, *STEEL, *EPOXY COMPOSITES, *GRAPHITED MATERIALS, *GALVANIC CORROSION, METALS, COMPOSITE MATERIALS, GRAPHITE, ALLOYS, COATINGS, PAINTS, EPOXY COMPOUNDS, POLYURETHANE RESINS, CURRENTS, EPOXY COATINGS, SALT WATER.

Subject Categories : Properties of Metals and Alloys
      Polymer Chemistry
      Coatings, Colorants and Finishes
      Laminates and Composite Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE