Austenitic steels

Austenitic steels are Iron-Carbon-Chromium-Nickel alloys, sometimes containing additional elements like Molybdenum, Titanium and Niobium, which are carefully balanced to preserve the austenitic structure even at room temperature. Due to the high proportion of valuable components (Ni, Cr, Mo, Ti, Nb), austenitic stainless steels are one of the priciest steels commonly used.

In the AISI classification, austenitic steels belong to the 300 series, and variations in Nickel content distinguish different grades within this family. The basic composition comprises 18% Chromium and 8% Nickel, classified as AISI 304, or 18/8, while the addition of 2-3% Molybdenum improves its resistance to corrosion, resulting in the AISI 316 or 18/10 classification.

Austenitic steels have a low carbon content, typically up to around 0.08%. However, there are softer variants with Carbon content as low as 0.03%, identified by a final "L" in the abbreviation, such as AISI 304L or 316L (Low Carbon).

These steels have a crystalline structure featuring a face-centred cubic lattice (FCC).