904L (UNS N08904 / W.Nr. 1.4539)

904L alloy (UNS N08904 / W.Nr. 1.4539) is an austenitic stainless steel designed for a middle to high level of corrosion resistance. The alloy contains high levels of chromium and nickel with additions of molybdenum and copper to provide added corrosion resistance in certain media. The alloy is produced to low carbon levels for use in the welded condition as in welded vessels and other large and complex fabrications.

Equivalent Grades

AISI 904LN08904X1NiCrMoCu25-20-51.4539

Chemical Composition, %


Typical Physical and Mechanical Properties (RT, Annealed)

Density, g/cm3Melting Point, ℃Tensile Strength, MPaYield Strength, MPaELongation, %Hardness, HB

Available Products and Specifications

Rod, Bar, Wire and ForgingsASTM B625
Plate, Sheet and StripASTM A240
Pipe and TubeASTM A312
Welding Product
OthersASTM A193, ASTM A193


  • Non-magnetic
  • Stronger corrosion properties than Type 316L an 317L
  • Good resistance to sulphuric, phosphoric and acetic acids
  • High resistance to crevice and stress corrosion cracking
  • Excellent formability and weldability


Due to all of the benefits of using Type 904L stainless steel, it can be found in a number of applications in wide variety of critical industries including:

  • Cooling equipment for seawater
  • Chemical processing of sulphuric, phosphoric and acetic acids
  • Heat exchangers
  • Condenser tubes
  • Gas washing
  • Control and instrumentation
  • Oil and gas industry
  • Pharmaceutical production
  • Wiring in electrostatic precipitators