the 300 Series stainless steels including Types 304, 304L, 304H, 309, 310, 316, 316L, 316H, 321, 321H, 347, and 347H. The "L" and "H" suffixes refer to controlled ranges of low and high carbon content, respectively. These alloys are characterized by an austenitic structure. steels that do not have alloying elements intentionally added. However, there may be small amounts of elements permitted by specifications such as SA516 and SA106, for example that can affect corrosion resistance, hardness after welding, and toughness. Elements which may be found in small quantities include Cr, Ni, Mo, Cu, S, Si, P, Al, V and B. a family of alloys containing nickel as a major alloying element (>30%) including Alloys 200, 400, K-500, 800, 800H, 825, 600, 600H, 617, 625, 718, X-750, and C276.