Alloy 904L

Introduction :

Fully austenitic, 904L is less sensitive to sigma phases and precipitation ferrite than other straight and high molybdenum austenitic grades. 904L combines relatively high insides of nickel molybdenum, chromium, and copper to provide more overall corrosion resistance, especially in phosphoric and sulfuric conditions. As a result, this grade offers features such as:

  • A maximum service temperature of 450 ̊ C (824 ̊ F).
  • Resilience against stress corrosion cracking.
  • High resistance to crevice corrosion and pitting.
  • Easy to weld and high formability
  • More protection against intergranular corrosion.
  • Very good resistance to stress corrosion cracking.

Chemical Composition for Alloy 904L

C Cr Cu Mn Mo Ni P S Si
Max Max Max Max Max
0.02 19.0 – 23.0 1.0 – 2.0 2.0 4.0 – 5.0 23.0 – 28.0 0.045 0.035 1.0

Physical Properties for Alloy 904L

Grade Density
Elastic Modulus
Mean Co-eff of Thermal Expansion (µm/m/°C) Thermal Conductivity
Specific Heat 0-100°C
Elec Resistivity
0-100°C 0-315°C 0-538°C At 20°C At 500°C
904L 7900 190 15 11.5 500 952


Mechanical Properties for Alloy 904L

Grade Tensile Strength (MPa) min Yield Strength 0.2% Proof (MPa) min Elongation (% in 50mm) min Hardness
Rockwell B (HR B) Brinell (HB)
904L 490 220 36 70-90 typical 150


Alloy 904l Avaliability

Alloy 904l Specifications

Alloy 904l Tensile Requirements