Glossary

Zinc-plated steel is carbon or alloy steel that has been coated with a thin layer of zinc to provide corrosion resistance and enhanced durability. The zinc acts as a protective barrier between the steel and the surrounding environment, preventing moisture and oxygen from reaching the steel surface — two key factors that cause rust and oxidation.

The coating process, called electroplating (or electro-galvanizing), involves immersing the steel part in a zinc salt solution and passing an electric current through it. This deposits a thin, even layer of zinc—usually between 5 to 25 microns thick—onto the steel surface. The resulting finish is typically bright silver, bluish, or yellowish depending on the post-treatment (such as clear, blue, or yellow chromate passivation).

Zinc-plated steel offers two types of corrosion protection:

- Barrier protection, where the zinc layer physically seals the steel from air and moisture.

- Sacrificial protection, where zinc, being more reactive than iron, corrodes first when the surface is damaged or scratched—effectively protecting the underlying steel from rust.

This makes zinc-plated steel a cost-effective choice for fasteners, brackets, bolts, nuts, washers, and hardware used in automotive, construction, machinery, and general manufacturing applications. However, while it resists corrosion better than bare steel, zinc plating is not as durable as hot-dip galvanizing, which provides a much thicker zinc layer and better long-term outdoor protection.