Zinc Coating—Alcoa

12-YEAR INSPECTION RESULTS OF ATMOSPHERIC EXPOSURE TESTS ON METALLIZED ZINC COATED CARBON STEEL PANELS 

COLUMBUS, OHIO URBAN Base metal shows red rust on 3% of the front of the panels. Sprayed me shows red rust stain on 60 % of the remainder of the front Back of panels shows a genertu very thin white rust Base metal not attacked. Sprayed metal inmet. Vinyl seal coat unaffected. Base metal shows red rust staining Sprayed metal shows red nut staining on 60 % of the frooc surface. CR seal coat dissipated on front Seal coat on back unaffected. Base metal not attacked. Sprayed metal intact, but shows very thin white ruR on front and back of panels. 

KURE BEACH. NORTH CAROLINA (800-fclot) SALT-AIR Base metal not attacked. Sprayed metal oo front of panels shows very thin white rust, which is present as horizontal stnpesL Backofpanelt shows a scry thin white msc Base metal not attacked. Sprayed metal intact Vinyl seal coat unaffected. Base mcml not attacked. Spmyed metal on front of panels shows a very thin white rust Spmyed metal intact on bade CR seal coat is completely dissipated on both front and back of panels. Base meial not sttacked. Spmyed menu shows traces of vesy chin whist ruR on front and beck ofpensls. 

COLUMBUS. OHIO URBAN Same as Type 2. Base meal Dot stacked. Sprayed meal ioact. CR seal coal dissipated on front of paaels showing ven tbio white rust. Seal coat on back of panels tuaflectad. Same u Type 4. Base meal noc stacked. Sprayed meal loan. Vinyl seal coat on front of panels shows a very light deposit sain. Seal coat oo back of panels unaSeoed. 

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