Type 304 (UNS S30400)

Description

Type 304 stainless steel contains approximately 18% chromium and 8% nickel and is the most commonly specified stainless steel used throughout the world.  Type 304 is a versatile, general purpose stainless steel with good resistance to atmospheric corrosion, and to many chemicals and food and beverages.  These grades can be specified in the annealed condition where they have very good formability.  Higher nickel versions can be specified to enhance multi-stage deep drawing characteristics.  Type 304 is non-magnetic in the annealed condition but may become slightly magnetic as a result of cold working.

Type 304 can be dual certified as 304L when the composition meets the lower carbon limit of 304L and the slightly higher strength levels of 304.  Type 304L should be specified for welded applications as the low carbon version eliminates chromium carbide precipitation and enhances the corrosion resistance in the as-welded condition.

Chemical Composition

Chemical Composition (wt%) limits as specified in ASTM A276 and ASME SA276*

Carbon 0.08 Silicon 1.00
Chromium 18.0-20.0 Phosphorus 0.045
Nickel 8.0-11.0 Sulfur 0.030
Manganese 2.00    

*Maximum, unless range is indicated

Physical Properties

Physical properties for Type 304 Stainless Steel

Density, lb/in3 0.285
Modulus of Elasticity, psi 28 x 106
Coefficient of Thermal Expansion, 68-212˚F, /˚F 9.2 x 10-6
Thermal Conductivity, Btu/ft hr ˚F 9.4
Specific Heat, Btu/lb ˚F 0.12
Electrical Resistivity, Microhm-in 28.3

Mechanical Properties

Mechanical property requirements for hot finished product as specified in ASTM A276 and ASME SA276

Yield Strength, min. (ksi) 30
Tensile Strength, min. (ksi) 75
Elongation, min. (%) 40

Standards

Typical standards for Type 304 Stainless Steel

ASTM A276
ASTM A479
ASME SA276
ASME SA 479