Adding nickel is the classic way of preserving an austenitic structure in stainless steel. However, adding manganese, combined with nitrogen, can have the same effect – and at lower material cost.
Chrome-manganese grades are characterised by having a considerably reduced nickel content. They also see the addition of manganese and, often times, nitrogen and copper too. This reduced nickel content reduces the maximum content possible in the alloy. However, less chromium means less corrosion resistance, thus limiting the types of applications that this stainless steel can be used for.
Not only are chrome-manganese stainless steels significantly cheaper from a material cost point-of-view, depending on their chemical composition, they also offer good formability (ductility) and/or strength.