Galvanized steel wire refers to any steel wire product that has subjected to a galvanizing process to improve its resistance to corrosion. This process typically involves dipping the finished wire product into a bath of heated zinc compound to form a scratch- and corrosion-resistant coating across the entire surface of the wire. Although this coating is not considered to be a permanent anti-corrosion solution, it does greatly increase the wire's resistance to rust and thus considerably prolongs its service lifespan. Galvanized steel wire is available in a wide range of gauges and lengths, and is used extensively in the construction industry and in the industrial, do-it-yourself, and agricultural sectors.
Galvanizing is a particularly effective method of producing low cost, corrosion-resistant steel and iron products. Carbon steel and iron items are far more cost effective than similar stainless steel products, and the galvanizing process itself is not particularly costly. Galvanizing also offers very good corrosion protection so finished products are effective and cheap.
The galvanizing process protects products such as galvanized steel wire in the several ways. The first line of defense is formed by the physical barrier created by the galvanized layer. The second and most effective part of the anti-corrosion process involves what is known as "sacrificial anode" protection. The zinc coating is far less corrosion resistant than the steel, which causes it to be consumed by corrosion first, protecting the underlying wire.
One of the best characteristics of galvanized steel wire is the fact that, should the galvanized coating be scratched through to the underlying steel, it will continue to cathodically protect the exposed steel from corrosion. This makes the galvanizing process a particularly efficient anti-corrosion treatment.
New galvanized steel wire is easily recognized by its matte gray, spangled surface. This spangle or crystalline appearance is a product of the size of the zinc particles in the hot dip solution and the cooling rate after the wire has been dipped. In other galvanized products, these characteristics can be manipulated to give an attractive aesthetic finish to the end product.
Once the wire has been exposed to the elements for some time, the wire will turn a dull, darker gray color which is an indication that the coating is corroding and doing its job as sacrificial anode. At this point, should the wire be nicked or scratched, it will take extended exposure to cause the steel to rust due to the continued cathodic protection offered by the galvanized coating.
Galvanized steel wire is extensively used as a binding or baling fastener, in the production of moderate strength steel ropes, and as reinforcement in multi-core electrical cables. Its low cost and ease of production makes this wire ideal for mass produced corrosion resistant wire products. It is an indispensable industrial, agricultural, and DIY fastening and reinforcement standard.