Steel its tensile strength and make the austenite form of the iron-carbon solution more stable, chromium increases hardness and melting temperature, and vanadium also increases hardness while making it less prone to metal fatigue. To inhibit corrosion, at least 11% chromium is added to steel so that a hard oxide forms on the metal surface; this is known as stainless steel. Tungsten slows the formation of cementite, keeping carbon in the iron matrix and allowing martensite to preferentially form at slower quench rates, resulting in high speed steel. On the other hand, sulfur, nitrogen, and phosphorus are considered contaminants that make
SAE 304 stainless steel by SAE International as part of its SAE steel grades. Outside of the US it is commonly known as A2 stainless steel, in accordance with ISO 3506 for fasteners. In the commercial cookware industry it is known as 18/8 stainless steel. In the unified numbering system it is UNS S30400. The Japanese equivalent grade of this material is SUS304.. It is also specified in European norm 1.4301. 304 stainless steel has excellent resistance to a wide range of atmospheric environments and many corrosive media. It is subject to pitting and crevice corrosion in warm chloride environments and to stress corrosion