304 stainless steel is the most common stainless steel . The steel contains both chromium (between 18% and 20%) and nickel (between 8% and 10.5%) metals as the main non- iron constituents. It is an austenitic stainless steel . It is less electrically and thermally conductive than carbon steel . It is magnetic, but less magnetic than steel. It has a higher corrosion resistance than regular steel and is widely used because of the ease in which it is formed into various shapes.
304 Stainless Steel Chemical Composition, % | ||||||||
Standard | AISI (UNS) | C≤ | Si≤ | Mn≤ | P≤ | S≤ | Cr | Ni |
ASTM A276/A276M | 304 (S30400) | 0.08 | 1.00 | 2.00 | 0.045 | 0.030 | 18.0-20.0 | 8.0-11.0 |
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 cracking above about 60°C. It is considered resistant to pitting corrosion in water with up to about 400 mg/L chlorides at ambient temperatures, reducing to about 150 mg/L at 60°C.
304 stainless steel is also very sensitive at room temperature to the thiosulfate anions released by the oxidation of pyrite (as encountered in acid mine drainage ) and can undergo severe pitting corrosion problems when in close contact with pyrite - or sulfide -rich clay materials exposed to oxidation.
304 stainless steel is used for a variety of household and industrial applications such as food handling and processing equipment, screws,
machinery parts, utensils, and
exhaust manifolds
. 304 stainless steel is also used in the architectural field for exterior accents such as water and fire features. It is also a common coil material for vaporizers.