How Galvanization Works
Galvanization provides electrochemical protection for steel. Zinc is used to generate galvanic electricity, which is electricity produced by chemical action. When zinc and steel are in electrical contact with each other, the zinc oxidizes while the current prevents the steel from oxidizing, thus lengthening the life of galvanized steel products.
Hot-dipped galvanized steel is produced by running a cold rolled substrate through a molten bath of zinc. Free zinc-coated type steel — designated with a G — is more corrosion-resistant than the alloy, and the degree of resistance is related to the amount of zinc coating (the higher the G number, the greater the corrosion resistance). The alloy type — with an A designation — has a zinc/iron alloy coating and is more easily spot welded.
Hot-dipped galvanized steel is typically used in applications where corrosion resistance is a necessity, such as building panels, farm equipment, electronic equipment, ductwork, and garage and entrance doors.
Hot-Dipped (ASTM A653)
- Gauges ranging from .0142 to .070 (our limit)
- Grades ranging from EDDS to C5 type B to High-Strength Low Alloy
- Coating weights of G-40 (.10 oz/ft2 total both sides) to G-210 (2.10 oz/ft2 total both sides)
- Finishes from no spangle (dull gray color) to regular spangle (bright and shiny)
Electrogalvanized steel is produced by applying zinc to the surface of the cold rolled substrate through an electroplating process. The surface of this product is a smooth, dull gray, and it can be chemically treated to improve the adhesion of paint.