CHROMATE LEACHING UNDER ACCELERATED WEATHERING CONDITIONS ON MATERIALS - COATINGS AND FINISHES - ORGANIC- PRIMERS, CORROSION INHIBITING - LACQUER AND EPOXY RESIN VEHICLE - ZINC CHROMATE PIGMENT

The preparation of Chromium 51 tagged zinc chromate pigment in accordance with Mil-P-8585 for use in lacquer vehicle primer, and a proprietary calcium chromate pigment for use in epoxy resin vehicle primer is described along with the preparatis, *Paint primers, *Aluminum, Chromates, Zinc compounds, Calcium compounds, Epoxy resins, Varnishes, Labeled substances, Enamel coatings, Test methods, Humidity, Seawater, Climatic factors, Corrosion inhibition. The preparation of Chromium 51 tagged zinc chromate pigment in accordance with Mil-P-8585 for use in lacquer vehicle primer, and a proprietary calcium chromate pigment for use in epoxy resin vehicle primer is described along with the preparation of the corrosion inhibiting primers used. Radioactive counts were used to determine chromate losses, and weight differences were used to determine primer losses resulting from humidity cabinet and salt spray cabinet exposures. Chromate lo s from aluminum surfaces took place at a slow rate. During the first week in the humidity cabinet about 0.7% of the chromate ion left the surface per day and from the 6th through the 7th week, the rate of loss was almost constant at 0.1% per day. Leaching of Chromate from Aluminum Primers under Accelerated Weathering Conditions Investigation using Radioactive Tracers. See also AD-418 854.