904-6% Mo Main Characteristics and Applications

Data sheet for Alloy 904-6% Mo (UNS N08925, W. Nr. 1.4529), a super austenitic stainless steel, this alloy has a very similar composition to Alloy 904L, but the molybdenum content is increased to at least 6%, and there is a higher nitrogen content. Here are some of the key characteristics and applications of Alloy 904-6% Mo:

Main Characteristics

High Mo and Nitrogen Content: Significantly improves resistance to crevice corrosion and pitting corrosion, with a PREN value of approximately 43.

Resistant to Sulfuric and Phosphoric Acid: Suitable for use in sulphuric and phosphoric acid media containing chlorides and other contaminants that cause accelerated corrosion.

High Temperature Resistance to Acidic Chloride Solutions: Suitable for use in high temperature acidic chloride solutions found in the pulp and paper industry.

Resistant to Polluted Environments: Suitable for use in scrubbers and pollution control equipment. Marine Applications: Also well suited for use in offshore and other marine applications.

Application Areas

Chemical Industry: Used to handle sulphuric and phosphoric acid media containing chlorides and other contaminants.

Pulp and Paper: Used in environments where high temperature acidic chloride solutions are present.

Marine Engineering: Suitable for equipment and structures in marine environments.

Mechanical Properties

Ultra-Tensile Strength (UTS): 700 MPa0.2%

Yield Strength: 320 MPa

Elongation: 35%

Hardness (HV10): 180 - 220

Physical Properties

Density: 8100 kg/m³

Young's Modulus: 195 GPa

Thermal Conductivity: 13 W/(m·K)

Coefficient of Thermal Expansion: 0.000016 per Deg C

Processing Properties

Welding: Welding can be performed using processes commonly used for austenitic stainless steels. A "thoroughly alloyed" filler material of a nickel-based alloy is recommended.

Machining: This alloy is difficult to machine and form and will work harden. However, very good results can be obtained by selecting suitable tools and processing parameters.

Hot working: can be carried out in the temperature range of 1200 - 900°C, after which solution annealing (1170°C) and water quenching are necessary.

Composition (%)

Nickel (Ni): 25%

Chromium (Cr): 20%

Molybdenum (Mo): 6.3%

Copper (Cu): 0.9%

Manganese (Mn): 1.5%

Silicon (Si): 0.5%

Nitrogen (N): 0.20%

Carbon (C): 0.02%

Iron (Fe): Balance

If you want to know more, please contact me at Julie@gaoshengpipe.com