Does Galvanized Sheet Metal Rust

If the item is exposed to continually wet conditions the zinc develops a film known as white rust.

Does galvanized sheet metal rust.

Through a variety of experiments i ve come to learn a pretty consistent process for removing this galvanization and making the metal rust. Hot dipped galvanized steel and electroplated galvanized steel are made using different methods and their zinc galvanized coatings corrode completely differently. The zinc acts as a barrier preventing oxygen and water from reaching the steel so that it is corrosion protected. Metal is galvanized by adding a thin layer of zinc to its surface.

Galvanized steel in particular is often what is used in modern steel frame buildings. This generally prevents rust. Galvanization involves zinc which corrodes instead of the actual metal to prevent rust. In developed countries most larger cities have several galvanizing factories and many items of steel manufacture are galvanized for protection.

When the zinc is all gone this is when real rust sets in. Galvanized steel takes a long time to rust but it will eventually rust. I believe it has to have iron in it in order to rust and if it s galvanized stainless steel or some other type of metal that doesn t corrode then this process won t work. I love to incorporate tie plates and nail plates that are used in construction but in most cases this type of steel has a galvanized finish to prevent them from rusting.

Left untreated white rust corrodes the zinc and the metal underneath begins to rust exhibiting the more traditional brownish red color. Galvanized metal is coated with a layer of zinc to protect the iron or steel underneath. The zinc forms a barrier between atmospheric oxygen and the underlying iron or steel. Galvanized steel is designed not to rust so if you have a galvanized steel item that has rusted it means that the galvanization has worn off completely in those areas.

Galvanized steel has been used for almost 2 000 years because of its unrivaled ability to last a very long time and resist rust. Galvanized metal does rust eventually but it can take decades. Cool rolled sheet metal is also frequently galvanized. I learned this the hard way by trying to rust some galvanized buckets i had on hand and read up about it here.