Accession Number : ADA308063

Title :   Development of Nonchromate Corrosion Inhibitors for Coatings on Aluminum.

Descriptive Note : Final rept. Feb 90-Feb 93,

Corporate Author : LOCKHEED MISSILES AND SPACE CO INC PALO ALTO CA

Personal Author(s) : Ballin, L. J.

PDF Url : ADA308063

Report Date : DEC 1995

Pagination or Media Count : 54

Abstract : The objective of this study was to develop nonchromate substitutes equivalent to the chromate corrosion inhibitors formulated in primers and/or paints for the protection of high-strength aluminum alloys. Quaternary ammonium dimolybdate salts (Q-Mo) were found to prevent ocean-water salt-spray corrosion for 2000 hours, equivalent to the strontium chromate-filled epoxy-polyamide primer, MIL-P-23377. Quaternary ammonium nitrate, phosphate, and borates were included in the evaluations. However, the Q-Mo was superior in every regard. The dimolybdate quaternary ammonium salt is a developmental inhibitor of high purity containing less than 1000 ppm sulfate and 100 ppm chloride. Optimization of the molybdate in the primer was eminently successful in achieving the physical, corrosion, and fluid resistance, and working properties required for demonstration testing and evaluation.

Descriptors :   *CORROSION INHIBITION, *COATINGS, *ALUMINUM, TEST AND EVALUATION, OPTIMIZATION, HIGH RATE, ALUMINUM ALLOYS, RESISTANCE, CHROMATES, HIGH STRENGTH ALLOYS, PRIMERS, PURITY, CHLORIDES, AMMONIUM COMPOUNDS, FLUIDS, PAINTS, OCEANS, SALTS, SULFATES, INHIBITORS, QUATERNARY COMPOUNDS, STRONTIUM, BORATES, PHOSPHATES, NITRATES, MOLYBDATES, SALT WATER.

Subject Categories : Inorganic Chemistry
      Coatings, Colorants and Finishes
      Properties of Metals and Alloys

Distribution Statement : APPROVED FOR PUBLIC RELEASE