EVALUATION OF ZINC COATING PROCEDURES

This research project was conducted in order to compare the existing procedure of zinc coating by hot-dip galvanizing with the other zinc coating systems of painting and electroplating. Hardware coated by these processes was exposed to varied laboratory tests. Based upon the results of these tests, the protection afforded by the GS grade of electroplated hardware was determined to be equivalent to that of the hot-dip galvanized hardware having a coating thickness of approximately 2 ounces per square foot of surface area (0.061 g/sq cm). The LS grade of electroplated hardware was found to be inferior in performance to both the GS grade of electroplated and hot-dip galvanized hardware. The zinc-rich paints used as repair systems gave adequate protection to the hardware after being exposed in a hot and humid environment for 12 months. Results using the scanning electron microscope showed a distinct difference in the layer of zinc deposited on the steel surface using the electroplating and hot-dip galvanizing procedures. A four-year field evaluation has been completed. The results showed that generally all the zinc coatings were performing satisfactorily. /FHWA/

  • Record URL:
  • Supplemental Notes:
    • Conducted in cooperation with DOT, Federal Highway Administration.
  • Corporate Authors:

    Louisiana Department of Transportation and Development

    1201 Capitol Access Road, P.O. Box 94245
    Baton Rouge, LA  USA  70804-9245
  • Authors:
    • Lacinak Jr, H W
    • McMichael, K L
  • Publication Date: 1976-12

Media Info

  • Pagination: 31 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00179858
  • Record Type: Publication
  • Source Agency: Federal Highway Administration
  • Report/Paper Numbers: FHWA-LA-78-116 Final Rpt.
  • Contract Numbers: La. Study 72-1CH(B)
  • Files: TRIS, USDOT, STATEDOT
  • Created Date: Oct 12 1978 12:00AM