Alloy 316L (UNS S31603)

Alloy 316L is an austenitic stainless steel supplied in the hot worked and annealed condition. The addition of Mo provides the product with much improved corrosion resistance compared with Alloy 304, particularly with respect to pitting and crevice corrosion in chloride environments. Alloy 316L resists atmospheric corrosion, as well as, moderately oxidising and reducing environments. It also resists corrosion in polluted marine atmospheres. The alloy has excellent resistance to intergranular corrosion in the as-welded condition.

It also provides higher creep, stress-to-rupture and tensile strength at elevated temperatures than a basic Alloy 304. As a fully austenitic grade it possesses excellent toughness, even down to cryogenic temperatures. This low carbon version of Alloy 316 is immune from the sensitisation caused by the precipitation of carbides at grain boundaries when heated, resulting in its widespread use in larger section welded components. It is readily formed and machined, although its relative toughness means that better machining is generally achieved at lower speeds with heavier feeds.