- Author
- Baker, M. A.
- Title
- Three-Year Inspection of Nature-Tone Porcelain Enamels on Steel.
- Coporate
- National Bureau of Standards, Washington, DC
- Sponsor
- Porcelain Enamel Institute, Washington, DC
- Report
- NBS TN 707, December 1971, 16 p.
- Distribution
- Available from Government Printing Office
- Keywords
- acid resistance | color | continuity of coating | porcelain enamel | weather resistance
- Abstract
- A weather exposure test on nature-tone porcelain enamels on steel was initiated by the National Bureau of Standards and the Porcelain Enamel Institute in 1966. Laboratory measurements for changes in gloss and color were made after the enamels had been exposed for 0.5, 1 and 3 years at Kure Beach, North Carolina, Miami, Florida and Gaithersburg, Maryalnd. The average gloss and color retained for all 450 specimens exposed at 3 sites for 3 years were 90.5 and 99.1 respectively. There was a tendency for the enamels exposed at the marine sites to rust around pinhole-type defects. Scanning electron microscope studies of these defects showed a layer of readily corrodible enamel on the bottom of the defects. A high-voltage test for continuity of coating was effective in detecting specimens that were apt to rust during the first year's exposure.