AISI 904L is a low-carbon, high-alloy austenitic stainless steel formulated with nickel, chromium, molybdenum and copper. The copper addition greatly strengthens its resistance to strong acids such as sulfuric acid. Developed exclusively for highly corrosive service environments, this material avoids the gradual degradation that standard stainless steels suffer after long-term exposure to such harsh conditions.

Core Advantages

• Exceptional corrosion resistance under severely corrosive working conditions

• Outstanding resistance to various acids, including sulfuric acid

• Excellent resistance to pitting and crevice corrosion

• Superior resistance to stress corrosion cracking

• Extended service lifespan in harsh chemical service environments

• Non-magnetic under annealed condition

• Suitable for extreme industrial and marine corrosive environments

AISI 904L Equivalent Material Standards

• AISI (US): 904L

• BS (UK): 904S13

• DIN (Germany): 1.4539

• Commercial Grade: Uranus B6

• Euronorm: X1NiCrMoCu25.20.5

• AFNOR (France): Z2NCDU25-20

• UNS Number: N08904

Chemical Composition (Mass Percentage)

• Carbon (C): Max 0.02%

• Chromium (Cr): 19.00%–23.00%

• Nickel (Ni): 23.00%–28.00%

• Molybdenum (Mo): 4.0%–5.0%

• Silicon (Si): Max 1.0%

• Phosphorus (P): Max 0.045%

• Sulfur (S): Max 0.035%

• Copper (Cu): 1.0%–2.0%

• Iron (Fe): Balance

Mechanical & Physical Properties

• Typical Hardness: HRB 70–90

• Tensile Strength: 490 MPa

• Maximum Operating Temperature: 400°C

• Specific Gravity (Density): 8.00 g/cm³ (0.288 lb/in³)

• Mean Coefficient of Thermal Expansion (0–100°C): 15 μm/m·°C

• Magnetic Property: Non-magnetic