Stainless Steel 904L is a non-stabilised low carbon high alloy austenitic stainless steel. The addition of copper to this grade gives it greatly improved resistance to strong reducing acids, particularly sulphuric acid. It is also highly resistant to chloride attack – both pitting crevice corrosion and stress corrosion cracking. This grade is non-magnetic in all conditions and has excellent weldability and formability. The austenitic structure also gives this grade excellent toughness, even down to cryogenic temperatures. Stainless Steel 904L does have very substantial contents of the high cost ingredients nickel and molybdenum. Many of the applications in which this grade has previously performed well can now be fulfilled at lower cost by duplex stainless steel 2205 (S31803 or S32205), so it is used less commonly than in the past.
Chemical composition (average %)CSiMnCrMoNiCuN0,0200,500,7520,304,5025,101,500,06
StandardsDINAFNORUNSSIS1.4539 X1NiCrMoCu25-20-5Z2NCDU25-20N089042562
Mechanical properties at room temperature Condition: solution quenchedProductDimensions0.2% proof stress1% proof stress
Tensile strenghtElongation A5Impact strenght (ISO-V)mmN/mm² minN/mm² minN/mm²LQTLQTBI< 30—35——55—St.Sch< 160220250520-72040——85——St = Bars Sch = Forgings BI = Sheet or Plate L = Longitudinal Q = Transverse T = TangentialThe values for others products and dimensions shall be establishedin accordance with relevant specifications by agreement.
High – Temperature propertiesTemperature50°C100°C150°C200°C250°C300°C350°C400 °C0.2% proof stress N/mm² min1901751651551451351301251% proof stress N/mm² min220205195185175165160155
Physical propertiesDensity at20°C8.00 g/dmThermal conductivity at20°C12 W/(mK)Specific heat at20°C0.45 J/(gK)Electric resistivity at20°C1.00 Ohm mm/mModulus of elasticity at20°C197 x 10 N/mmMagnetic propertiesCan be slightly magneticThermal expansion between 20°C e …°C 10 m/(mK)Temperature10 m/(mK)100°C15.8200°C16.1300°C16.5400°C16.9500°C17.3Modulus of elasticity, 10 N/mm atTemperature10 N/mm20°C197100°C191200°C184300°C177400°C170500°C163
Corrosion Resistance Although originally developed for its resistance to sulphuric acid it also has a very high resistance to a wide range of environments. A PRE of 35 indicates that the material has good resistance to warm sea water and other high chloride environments. High nickel content results in a much better resistance to stress corrosion cracking than the standard austenitic grades. Copper adds resistance to sulphuric and other reducing acids, particularly in the very aggressive “mid concentration” range. In most environments Stainless Steel 904L has a corrosion performance intermediate between the standard austenitic grade 316L and the very highly alloyed 6% molybdenum and similar “super austenitic” grades. In aggressive nitric acid Stainless Steel 904L has less resistance than molybdenum-free grades such as Stainless Steel 904LL andStainless Steel 310L. For maximum stress corrosion cracking resistance in critical environments the steel should be solution treated after cold work. Heat Resistance Good resistance to oxidation, but like other highly alloyed grades suffers from structural instability (precipitation of brittle phases such as sigma) at elevated temperatures. Stainless Steel 904L should not be used above about 400C. Heat Treatment
Solution Treatment (Annealing) – heat to 1090-1175C and cool rapidly. This grade cannot be hardened by thermal treatment.
Welding
Stainless Steel 904L can be successfully welded by all standard methods. Care needs to be taken as this grade solidifies fully austenitic, so is susceptible to hot cracking, particularly in constrained weldments. No pre-heat should be used and in most cases post weld heat treatment is also not required. AS 1554.6 pre-qualifies Grade 904L rods and electrodes for welding of 904L. Fabrication Stainless Steel 904L is a high purity, low sulphur grade, and as such will not machine well. Despite this the grade can be machined using standard techniques. Bending to a small radius is readily carried out. In most cases this is performed cold. Subsequent annealing is generally not required, although it should be considered if the fabrication is to be used in an environment where severe stress corrosion cracking conditions are anticipated.
APPLICATIONS FIELD :
Industry
Applications
Industry
Applications
Chemical
Heat Exchanger,Boiler
Sugar
Evaporators, Condensers, Driers
Petrochemicals
Condensers
Automobiles
Muffler Tubes Hydraulic Tubing
Refineries
General Piping
Construction
Architectural Furniture
Fertilizers
Pressure Vessels
Pharmaceuticals, Dairy, Food & Beverages
Machineries Process Piping, Stainless Steel U Tubes
Paper & Pulp
Industrial Equipments
Submersible Pumps
Pump Casing Applications
Engineering
Machineries Instrumentation Tubing
Oil and Gas
Stainless Steel pipes, Stainless Steel Pipe Fittings, Stainless Steel Flanges
wilsonpipeline Pipe Industry Co., Limited offers a comprehensive range of 904L Stainless Steel Pipes and 904L Stainless Steel Tubes.
904L Stainless Steel Pipes and 904L Stainless Steel Tubes Product Range 904L Stainless Steel Pipes and 904L Stainless Steel Tubes Specifications: ASTM A/ASME SA 269/677 904L Stainless Steel Pipes and 904L Stainless Steel Tubes Sizes (Seamless): 1/2″ NB – 8″ NB 904L Stainless Steel Pipes and 904L Stainless Steel Tubes Sizes (ERW): 1/2″ NB – 24″ NB 904L Stainless Steel Pipes and 904L Stainless Steel Tubes Sizes (EFW): 6″ NB – 100″ NB
904L Stainless Steel Pipes and 904L Stainless Steel Tubes Wall Thickness available: Schedule 5S – Schedule XXS (heavier on request) 904L Stainless Steel Pipes and 904L Stainless Steel Tubes Other Materials Testing: NACE MR0175, H2 SERVICE, OXYGEN SERVICE, CRYO SERVICE, etc
These properties are specified for flat rolled product (plate, sheet and coil) in ASTM B625. Similar but not necessarily identical properties are specified for other products such as pipe, tube and bar in their respective specifications.
Source: wilsonpipeline Pipe Industry Co., Limited (www.wilsonpipeline.com)
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