A low carbon form of 304 with 0.030-0.035% carbon maximum, designed primarily to avoid intercrystalline corrosion after welding. The tensile strength is somewhat lower than type 304 which is an economic balance of alloying elements ensuring good formability, corrosion resistance, toughness and mechanical properties. Its corrosion resistance in unpolluted atmospheres and freshwater environments is excellent but some attack may occur in costal/marine locations and damp industrial atmospheres. Not recommended for use in seawater environments.
The addition of 2-3% Moybdenum in this grade confers increased corrosion resistance in industrial and coastal environments, together with improved elevated temperature properties. The resistance to pitting when actually immersed in cold seawater is limited. Ahigher nickel content of 12% is used to maintain an austenitic structure.