Accession Number:

ADA164788

Title:

The Effects of Steel Profile and Cleanliness on Coating Performance

Descriptive Note:

Technical note Oct 1979-Sep 1984

Corporate Author:

NAVAL CIVIL ENGINEERING LAB PORT HUENEME CA

Report Date:

1986-01-01

Pagination or Media Count:

34.0

Abstract:

A 5-year study was conducted in cooperation with the Steel structure Painting Council SSPC to determine surface profile and cleanliness requirements for long-term performance of generic coating systems currently used on Navy shore facilities. The experimental design included two levels of cleaning white metal finish and commercial finish, four levels of profile height low, medium, high, and very high, eight levels of abrasive eight different abrasives, and six levels of generic coating system alkyd, acrylic latex, vinyl, eopxy, coal tar epoxy, and inorganic zincvinyl. Replicate sets of the different variations were exposed in a salt fog chamber and at test exposure sites in a tropical marine atmospheric environment at Kwajalein Atoll in the Marshall Islands in an industrial environment at Pittsburgh, Pa and in a relatively mild marine atmospheric environment at Kure Beach, N.C. After 15 months of exposure at Kwajalein, relatively little change had occurred in the overall loss in bonding strength occurred. Significantly different variations occurred between the different coating systems, and the range of values was greatly reduced. Salt fog exposure had a much greater effect on loss of adhesion than did natural exposure for 57 months for the periods measured. Levels of statistical significance for performance at Kwajalein varied greatly with time and were much greater on scribed than unscribed specimens. Coating system was the most significant variable, followed by abrasive and profile height, and lastly by level of cleaning. Thus, profile was more important than cleanliness in field performance as well as in the laboratory salt fog testing and the adhesion study.

Subject Categories:

  • Coatings, Colorants and Finishes

Distribution Statement:

APPROVED FOR PUBLIC RELEASE