IntroductionStainless steel grade Duplex 2304 is a duplex
stainless steel type with a structure that is a balance of ferritic
and austenitic. It has high strength and toughness, resistance to
stress corrosion cracking, high thermal conductivity, low thermal
expansion, and easy fabrication. It is recommended that this steel
is not used in areas where the steel would be exposes to
temperatures over 1058C (570F) for prolonged periods.The following
datasheet provides an overview of stainless steel grade Duplex
2304.Chemical CompositionThe chemical composition of stainless
steel grade Duplex 2304 is outlined in the following
table.ElementContent (%)
Iron, Fe72.679
Chromium, Cr23
Nickel, Ni4
Molybdenum, Mo0.20
Nitrogen, N0.1
Carbon, C0.02
Sulfur, S0.001
Mechanical PropertiesThe mechanical properties of stainless
steel grade Duplex 2304 are displayed in the following
table.PropertiesMetricImperial
Tensile strength 600 MPa 87000 psi
Yield strength (@strain 0.200 %) 400 MPa 58000 psi
Modulus of elasticity200 GPa29000 ksi
Shear modulus (@temperature 20C/ 68F)75.0 GPa10900 ksi
Poissons ratio0.3330.333
Elongation at break 25 % 25 %
Hardness, Rockwell C 20.0 20.0
Hardness, Brinell180 - 230180 - 230
Other DesignationsEquivalent materials to stainless steel grade
Duplex 2304 are given below: ASTM A240 ASTM A276 ASTM A480 ASTM
A789 ASTM A790 DIN 1.4362Manufacturing ProcessMachining of
stainless steel grade Duplex 2304 is performed at low speeds, and
constant feeds help to reduce its tendency to work harden. This
material is tougher than grade 304 and 316 stainless steels due to
its long stringy chip. Chip breakers are recommended. Unlike the
300 series stainless steel, Duplex 2304 steel requires more
pressure while performing forming due to its higher yield strength.
Its low ductility characteristic tends to make it difficult to
perform forming operations.Welding can be performed using most of
the traditional methods such as gastungsten arc welding (GTAW),
submerged arc welding (SAW), and gasmetal arc welding (GMAW). The
filler metal should be a balanced of ferrite/ austenite type like
2205 or 2304.Hot working can be done after heating the material to
954-1093C (1750-2000F), which is followed rapid cooling. Annealing
after working is recommended. For annealing, the material is heated
to 930-1050C (1710-1920F) and then rapidly
quenched.ApplicationsStainless steel grade Duplex 2304 is used by
various industries including pulp and paper, coal handling, potash,
food and beverage, and waste water.The specific applications are as
follows: Bridges Storage tanks Water heaters Heat exchangers
Pressure vessels Feedwater tubes Heat exchangers Flue-gas cleaning
Seawater systems Desalination plants Parts for structural design
Rotors, impellers and shafts Firewalls and blast walls on offshore
platforms Cargo tanks and pipe systems in chemical tankers Piping
and instrumentation tubing for general service
