These are the most popular of the stainless steels because of their ductility, ease of working and good corrosion resistance; they are derived from the 18Cr-8Ni stainless steel Type 304. The other grades are developed to provide special corrosion resistance properties by adding Molybdenum, Chromium and/or decreasing Carbon content (L grades).

Addition of stabilizing elements like Titanium or Niobium (Columbium) provides better weldability. Addition of Nitrogen increases mechanical strength as for grades 304N or 316N.

They are also available in the heat resistant version (H grades) with a higher Carbon content and coarser grain size to improve creep resistance. They can be used up to 870°C /1600°F.

They also exhibit good ductility and toughness even at cryogenic temperatures.

All are essentially nonmagnetic in the annealed condition, although some may become slightly magnetic by cold working.

The major weakness of the austenitic stainless steels is their susceptibility to chloride stress corrosion cracking (SCC).

They serve a wide range of applications: architecture, food processing environments, organic and inorganic chemicals environments in the process industry, nitric acid and sulphuric acids at moderate temperature and concentrations, equipment for use at cryogenic temperatures, storage and transportation of liquefied gases, transportation, water and wastewater treatment…