304

Applications

Alloy 304 Stainless Steel is used in a wide variety of home and commercial applications, including:

•  Chemical containers, including for transport
•  Food processing equipment, particularly in beer brewing, milk processing, and wine making
•  Heat exchangers
•  Architectural trim and molding
•  Woven or welded screens for mining, quarrying & water filtration
•  Automotive and aerospace structural use
•  Nuts, bolts, screws, and other fasteners in the marine environment
•  Construction material in large buildings

Standards

•  ASTM/ASME: UNS S30400 / S30403
•  EURONORM: 1.4301 / 1.4303
•  AFNOR: Z5 CN 18.09 / Z2 CN 18.10
•  DIN: X5 CrNi 18 10 / X2 CrNi 19 11

Corrosion Resistance

•  Resistance to moderately aggressive organic acids is a result of the 9 to 11% nickel that the 304 alloys contain.
•  Resistance to corrosion in oxidizing environments is a result of the 18 to 19% chromium that the 304 alloys contain.
•  The 304, 304L, and 304H may be considered to perform uniformly in most corrosive environments.

Heat Resistance

•  Continuous use of 304 in the 800-1580°F range is not recommended if subsequent aqueous corrosion resistance is important.
•  Good oxidation resistance in intermittent service to 1600°F and in continuous service to 1690°F.

Welding Characteristics

Excellent welding properties; post-weld annealing is not required when welding thin sections. Two important considerations in producing weld joints in the austenitic stainless steels are:

1.  avoidance of cracking
2.  preservation of corrosion resistance

Processing - Hot Forming

•  To forge, heat uniformity to 2100 / 2300 °F
•  Do not forge below 1700 °F
•  Forging can be air cooled without danger of cracking

Processing - Cold Forming

•  Its austenitic structure allows it to be deep-drawn without intermediate annealing, Making this the stainless steel grade of choice in the manufacturing of sinks, hollow-ware and saucepans.
•  These grades work harden rapidly. To relieve stresses produced in severe forming or spinning, parts should be full annealed or stress relief annealed as soon as possible after forming.

Machinability

•  The use of chip breakers is advised since the chips can be stringy. Stainless steel work harden rapidly, heavy positive feeds, sharp tooling, and a rigid set-up should be used.

Chemical Properties

Mechanical Properties

Physical Properties