Created on 08.22

How to Choose the Right Zinc Coating Thickness for Galvanized Iron Wire Based on Environmental Corrosion Levels

The selection of galvanized iron wire depends on matching the zinc coating thickness with the environmental corrosion level. The zinc layer protects the iron base through sacrificial anode mechanism, delaying rust formation. Generally, the more corrosive the environment, the thicker the zinc coating required.

In mild corrosion environments (e.g., dry indoors, rural atmospheres), a zinc coating of 20-50 g/m² (approx. 3-7μm) is sufficient. These environments have minimal corrosive factors, and the zinc layer primarily handles occasional humidity or weak acids/alkalis.

For moderate corrosion environments (e.g., urban atmospheres, light industrial areas, high-humidity zones), a higher level of protection is needed, with a zinc coating of 50-130 g/m² (7-18μm). Such environments often contain sulfur dioxide or salt particles, requiring a thicker zinc layer to extend service life.

In severe corrosion environments (e.g., coastal regions, industrial zones, chemical plants, or high-temperature/humidity areas), the zinc coating should be at least 130 g/m² (up to 250 g/m² or more). High concentrations of chlorides, strong acids, or alkalis accelerate zinc consumption, necessitating a thick coating for durable protection.

Additionally, mechanical stress in application scenarios should be considered: high friction or bending requires good zinc adhesion and toughness. Refer to international standards (e.g., ISO 1461) or consult suppliers, and use corrosion tests (e.g., salt spray testing) to quantify needs, ensuring optimal durability and cost-effectiveness for galvanized iron wire in specific environments.