The overarching family of stainless steel is broken up into five distinct subfamilies, each occupying one of three crystal structures. In previous blog posts, we have explored the chemical compositions and physio-mechanical characteristics of both austenitic and martensitic stainless steels; two of the most ubiquitous alloys worldwide for fabricating corrosion-resistant structures and components. In this blog post, Masteel explores a third stainless steel subfamily in more detail: ferritic stainless grades.

What is Ferritic Stainless Steel?

Ferritic stainless steel occupies a body-centered cubic (BCC) granular structure that is typical of pure iron at room temperature. In terms of its microstructural arrangement, it is most closely linked to the martensitic subfamily of stainless steels, although they are dissimilar in terms of their chemical composition.

Typical ferritic stainless steels are low in both carbon (C) and nickel (Ni), often comprising as little or less than 1% of either mineral. Instead, ferritic grades feature elevated levels of corrosion-resistant chromium (Cr). Standard ferritic stainless steels contain approximately 12—20%, while specialized grades with as much as 29% chromium are also available.

Owing to their low carbon content, ferritic stainless steel grades cannot be hardened through heat treatment and must be provided in an annealed state. They can be strengthened through cold-working, however, and exhibit beneficial ferromagnetic characteristics.

The Importance of Ferritic Stainless Steels

Owing to their reduced nickel composition, ferritic stainless steel grades represent one of the most cost-effective solutions for corrosion-resistant applications. They boast inherent resistance to stress corrosion cracking, and thin sections of the material are readily formed and welded. Thicker sections may suffer a loss of functionality after welding, so ferritic stainless steels are typically utilized for small- medium-sized components with excellent corrosion-resistant properties.

Applications of Ferritic Stainless Steels

Ferritic stainless steels are impervious to oxidation and inherently resistant to a broad range of corrosives, boasting decent formability and good strength characteristics. These stainless steel grades are often used in commercial engineering of vehicle undercarriages and domestic appliances. Automotive exhaust components and catalytic converter cases are regularly fabricated from ferritic stainless steels, as are common utensils, and piping for sinks and dishwashers.

Stainless Steels from Masteel

Masteel is one of the UK’s leading suppliers of stainless steel grades for a broad range of industrial and engineering applications. We have developed a robust supply line that spans the highest quality steel mills in Europe and a reliable, global distribution network. If you would like to learn more about the various stainless steel subfamilies, please explore our previous posts:

Otherwise, contact us directly with any more questions.