Your search did not yield any results

Site Pages

Dr. Galv KnowledgeBase


Mechanical plating consists of a flash coating of copper followed by the zinc coating. Coating thickness requirements contained in ASTM Specification B 695 range from 0.2 to 4.3 mils (5 to 110 µm). While thicker coatings are possible, the common thickness on commercial fasteners is 2 mils (50 µm). The coating has a density of about 0.45 oz/ft2/mil compared to the hot-dip galvanized coating density of about 0.6 oz/ft2/mil. The hot-dip coating has over 30% more zinc per unit volume than a mechanical coating.

The coating, on a micro cross-section, appears to consist of flattened particles of zinc loosely bonded together. The mechanical bond between zinc and steel, and zinc to zinc in this process is weaker than the metallurgical bond found in hot-dip galvanizing. Edge, corner, and thread coating thicknesses are usually lower due to minimal peening action at these locations.

See Also:
Zinc Coatings Publication

Was this answer helpful? YES       | NO

Are you still looking for the right answer? Ask an Expert