Ferrous

Ferrous describes metals and alloys that contain iron as a principal element. The term comes from ferrum, the Latin name for iron, and is used to distinguish iron-containing materials from non-ferrous metals such as aluminum or copper.

Ferrous metals are typically strong, hard, and dense and are widely used in construction and manufacturing. They are often magnetic and tend to corrode when exposed to moisture unless protected. Iron readily forms various alloys by alloying with carbon and other elements.

Common ferrous materials include steel (an iron-carbon alloy that may also include other elements), cast iron (iron with higher carbon content), and wrought iron. Stainless steel is a ferrous alloy containing chromium that improves corrosion resistance; grey iron and ductile iron are iron-based cast products with graphite networks or nodules.

Due to their properties, ferrous materials are extensively employed in structural components, automotive parts, tools, machinery, and pipelines. They are also highly recyclable; magnetic separation is often used to separate ferrous scrap from nonferrous materials.

In chemistry, ferrous denotes iron in the +2 oxidation state (Fe2+), as in ferrous sulfate. The related term ferric denotes Fe3+.