While steel is undoubtedly one of the more popular construction materials, it’s not without its shortcomings. Steel is vulnerable to corroding.
Corrosion is an electro-chemical reaction that appears in several forms, such as chemical corrosion and atmospheric corrosion, the latter of which is the most common form. When acidic substances (including water) come in contact with metals, such as iron and/or steel, rust begins to form. Without protection, steel will rust due to atmospheric conditions over time. The degree of rust will depend on the environment that the product is in. Rust is an iron oxide (typically a red oxide) which is formed by the reduction and oxidation reaction of iron and oxygen, in the presence of water or air moisture
Corrosion resistant coatings protect metal components against degradation due to moisture, salt spray, oxidation or exposure to a variety of environmental or industrial chemicals.
Special anti-corrosion coatings are one of the best things you can use on steel to protect and preserve it. Not only are such coatings effective, they’re affordable as well. What makes them work is the coating creates a shield. This shield blocks the transfer of the electro-chemical charges that cause corrosion in the first place. Besides paint coatings, there are also dry powder coatings. These adhere to the metal when steel is heated up. Examples of powders used in steel heat treating include urethane, epoxy, nylon and acrylic.
Source – https://www.sst.net/specialty-steel-teating/