SS 904L

SS 904L

SS 904L is a high-alloy austenitic stainless steel that provides excellent corrosion resistance in highly aggressive environments, especially in the presence of sulfuric acid, phosphoric acid, and chlorides. Its unique composition makes it highly suitable for chemical processing, marine, and pollution control applications.

Chemical Composition of SS 904L

        Chromium (Cr)       19.0–23.0%
        Nickel (Ni)         23.0–28.0%
        Molybdenum (Mo)     4.0–5.0%
        Manganese (Mn)      2.0% max
        Silicon (Si)        1.0% max
        Carbon (C)          0.020% max
        Phosphorus (P)      0.045% max
        Sulfur (S)          0.03% max
        Iron (Fe)           Balance
    

Mechanical Properties of SS 904L

• Tensile Strength: 80,000–110,000 psi (550–760 MPa)
• Yield Strength: 30,000–45,000 psi (205–310 MPa)
• Elongation: 35% in 8 inches (200 mm)
• Hardness: 170–220 Brinell
• Modulus of Elasticity: 28,000 ksi (193 GPa)

SS 904L - Standard Specifications

SS 904L is a high alloy stainless steel known for its excellent resistance to corrosion, particularly in aggressive environments such as acidic or marine applications. Below are the recognized international standards for SS 904L.

1. ASTM Specifications for SS 904L

ASTM A240/A240M - Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications.

• Scope: Covers stainless steel plate, sheet, and strip of austenitic stainless steel, including SS 904L, intended for use in pressure vessels, reactors, and general applications requiring corrosion resistance.
• Grades Covered: SS 904L is listed as a grade for use in demanding corrosion-resistant applications.

2. EN Specifications for SS 904L

EN 10088-2 - Stainless Steels – Part 2: Technical Delivery Conditions for Sheet/Plate and Strip of Corrosion-Resistant Steels for General Purposes.

• Scope: Specifies the technical delivery conditions for stainless steels, including SS 904L, in sheet, plate, and strip forms for general applications.

3. UNS Designation

UNS Designation: N08904

The Universal Numbering System (UNS) assigns SS 904L the designation **N08904** for identification in international material databases.

4. DIN Specifications for SS 904L

DIN 1.4539 - This is the German material number for SS 904L. The grade is recognized under DIN for use in applications requiring resistance to aggressive environments.

5. BS (British Standard) Specifications

BS EN 10088-2:2005 - Stainless Steels – Part 2: Technical Delivery Conditions for Sheet/Plate and Strip of Corrosion-Resistant Steels for General Purposes. This is equivalent to the European standard **EN 10088-2** and specifies delivery conditions for SS 904L.

6. JIS (Japanese Industrial Standard)

JIS G4305 - Cold-Rolled Stainless Steel Plate, Sheet, and Strip. This standard is used in Japan and includes SS 904L for use in applications where corrosion resistance is critical.

7. ISO (International Organization for Standardization)

ISO 9444-2 - Stainless Steel for General Applications – Part 2: Sheet and Plate. This international standard covers stainless steels, including SS 904L, for general applications.

Summary of Key Specifications for SS 904L

Property	Standard Specifications
UNS Designation	N08904
ASTM	ASTM A240/A240M
EN	EN 10088-2
DIN	DIN 1.4539
BS	BS EN 10088-2:2005
JIS	JIS G4305
ISO	ISO 9444-2

Applications of SS 904L

SS 904L is ideal for use in applications where the material will be exposed to highly corrosive environments. Some of its common applications include:

• Chemical processing industries
• Marine environments and coastal applications
• Heat exchangers and condensers
• Pharmaceutical manufacturing
• Pulp and paper industry
• Pollution control systems