What is the character and application of 304 stainless steel?

General Properties

Alloy 304 a T-300 series stainless steel austenitic, which has a minimum of 18% chromium and 8% nickel. Type 304 has a maximum carbon of 0.07% . It is the standard “18/8 stainless” that is commonly found in pans and cooking tools. Alloy 304 is the most versatile and widely used alloy in the stainless steel family. Ideal for a wide variety of home and commercial applications, Alloy 304 exhibits excellent corrosion resistance and has a high ease of fabrication, outstanding formability. The austenitic stainless steels are also considered to be the most weldable of the high-alloy steels and can be welded by all fusion and resistance welding processes.

Specifications: UNS S30400


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

  • Kitchen benches, sinks, troughs, equipment, and appliances
  • 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
  • Dyeing industry


  • 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.


Properties of 304 Alloy

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.


  • 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.of cut below the work-hardened layer resulting from the previous passes.


Chemical Properties:

  C Mn Si P S Cr Ni N
304 0.07max 2.0max 0.75max 0.045max 0.03max min: 18.0 max: 20.0 min: 8.0 max: 10.5

Mechanical Properties:

GradeTensile Strength ksi (min)Yield Strength 0.2% ksi (min)Elongation %Hardness (Brinell) MAXHardness (Rockwell B) MAX
304 75 30 40 201 92

Physical Properties:

Thermal Conductivity
(BTU/h ft. °F)
(in x 10-6)
Modulus of
(psi x 106
Coefficient of
Thermal Expansion
°F x 10-6
Specific Heat
at 68°F: 0.285 9.4 at 212°F 28.3 at 68°F 28 9.4 at 32 – 212°F 0.1200 at 68°F to 212°F 2500 to 2590
  12.4 at 932 °F 39.4 at 752°F   10.2 at 32 – 1000°F    
    49.6 at 1652 °F   10.4 at 32 – 1500°F