Introduction

904L stainless steel combines molybdenum and copper with iron for tremendously increased resistance to reducing acids like sulphuric acid. It stands up extremely well to chlorides in the environment for low pitting and crevice corrosion, as well as stress corrosion cracking.

Applications

904L stainless steel is widely used in the chemical, pharmaceutical, oil and gas industries. Typical applications include tanks, valves, heat exchangers, flanges and manifolds. The addition of copper to the composition of 904L stainless steel aids its suitability for components such as tanks and other products used in handling sulphuric and phosphoric acid.

Quality Standard:
ASTM A182 Standard Specification for Forged or Rolled Alloy-Steel Pipe Flanges, Forged Fittings, and Valves and Parts
EN 10088 part3 stainless steel

All Grades Comparison

ASTM A182:904L

EN1008:1.4539

Chemical Composition(%)

904L    C:0.02max, Si:1.0max, Mn:2.0max, P:0.040max, S:0.030max, Cr:19.0-23.0, Ni:23.0-28.0, Mo:4.0-5.0, Cu:1.0-2.0, N:0.10max

1.4539  C:0.02max, Si:0.7max, Mn:2.0max, P:0.040max, S:0.010max, Cr:19.0-21.0, Ni:24.0-26.0, Mo:4.0-5.0, Cu:1.2-2.0, N:0.15max

Mechanical Properties (Annealed)

Hardness (HB):230max

Tensile Strength (Mpa):530-730

Yield Strength (Mpa):230-260

Elongation (%) (Long.):35min

Impact Value (J) (Long.):100min

Corrosion Resistance:

 Where a level of resistance to pitting corrosion better than 316 is required 904L stainless steel may be suitable. With its high nickel content at 25% it offers improved resistance to chloride stress corrosion cracking compared to other austenitic grades such as 304.

Welding:

 904L stainless steel can be welded using common fusion and resistance methods. A more highly alloyed filler is recommended to give the optimum corrosion properties in the weld. We recommend you contact your welding consumables supplier who should provide you full assistance and information on welding 904L stainless steel.

Mill′s test certificate

EN 10204/3.1 with all relevant data reg. chem. composition, mech. properties and results of testing.