Ferritic stainless steels generally do not contain nickel (Ni) and are a group of stainless steels with high chromium content (between 10.5% and 30%) and alloying elements such as molybdenum, titanium, and vanadium, which form carbides and stabilize the ferritic structure. The high chromium content typically provides ferritic stainless steels with very high corrosion resistance.

Ferritic stainless steels have mechanical and physical properties closer to their close relatives, carbon steels. Unlike austenitic steels, ferritic steels are magnetic, cannot undergo heat treatment due to their low carbon content, and are easily rolled. The only applicable heat treatment for these steels is annealing.

Recently, excessive price increases and fluctuations in alloying elements, especially nickel, have accelerated the development of ferritic steels. As a result, new ferritic grades have been developed that offer corrosion resistance comparable to austenitic steels but at a much lower cost, expanding their range of applications.

The most well-known ferritic grades are 430 and 442. Ferritic steels have a Body-Centered Cubic (BCC) crystal structure. Below are microstructures of ferritic stainless steels a) grade 409 and b) grade 439.