The stainless steel alloy designation of 1.4401 is the same as alloy SST-316. In fact, SST-316L also carries the name 1.4404. This alloy is a close second to 304 for commercial applications.

SST-316 owes it corrosion resistance to molybdenum. It is the addition to molybdenum which makes 316 an excellent choice for “marine” applications such as boat fittings and coastal paneling. It must be noted, however, that warm saltwater and warm chloride can cause pitting and corrosion.

A lower carbon content adds the “L” to Alloy SST-316L, while an “H” indicates a higher percentage of carbon. The designation “Ti” indicates that this version of 316 is suitable as a stabilized stainless steel alloy.

Alloy SST-316L is an excellent choice for heavy 6mm or higher applications and where welding will be required. Grade 316H, with its carbon content, is more suitable to uses that may experience high temperatures.

The score of 95 in the Rockwell Hardness B test is the same for any type of stainless steel SST-316. It is the lower carbon content alloy, SST-316L, which has the lower proof stress and tensile strength scores.

Stainless steel alloy 316 responds with increased hardness and strength to any type of cold working, including stamping, drawing and heading. It is important that rapid cooling annealing be performed once the cold working has finished to ensure that any internal material stresses are completely relieved.

Any type of hot working of stainless steel alloy SST-316 should only be performed at the correct temperature ranges. Those ranges are 1149 to 1260C. All hot work should stop if the temperature is less than 927 C.

Stainless steel alloy 316 does not respond at all to heat treatment. It does, however, respond well when properly machined; meaning that sharp cutting edges and liberal coolants or lubricants are employed.

The uses of alloy SST-316 are quite varied. It can be found in laboratory equipment and furnishings. It will also be on the coast in paneling and handrails. Breweries will also have equipment made from SST-316, as will many food processing plants. It is so versatile that it can be used as simple nuts and bolts or as life-saving surgical implants.

To learn more about the stainless steel alloy SST-316.