Marine grade stainless

Marine grade stainless, or SAE 316 stainless steel, is a molybdenum-alloyed steel and is the second most common austenite stainless steel (after grade 304). It is the preferred steel for use in marine environments because of its greater resistance to pitting corrosion than other grades of steel. The fact that it is negligibly responsive to magnetic fields means that it can be used in applications where a non-magnetic metal is required. In addition to molybdenum, 316 also contains a number of other elements in varying concentrations (see table below). Like other grades of stainless steel, marine grade stainless steel is a relatively poor conductor of both heat and of electricity when compared to metals and other conductive materials.

While 316 is not completely rust-proof, the alloy is more corrosion-resistant than other common stainless steels. Surgical steel is made from subtypes of 316 stainless steel.

Non-standard grades include 316H which has a "high" carbon content of greater than 0.04 % giving it a high creep rupture strength at high temperatures, 316L(Hi)N which is an extra-high nitrogen grade (0.16-0.30%), 316Ti which is stabilized by titanium, 316Cb which is stabilized by niobium, 316L-SCQ which is a high-purity version of 316L, and 316LS which specially adapted for surgical implants.

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