317LMN is a high-chromium austenitic stainless steel, nickel, molybdenum, and nitrogen alloy developed to offer superior corrosion resistance compared to traditional 316L and 317L.
The addition of molybdenum and nitrogen significantly increases resistance to pitting and crevice corrosion, making it ideal for environments containing chlorides and aggressive acids.
The alloy maintains excellent mechanical properties and can be used in the as-welded state without risk of carbide precipitation.

Reference standards:

• ASTM A240
• ASME SA240
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Chemical composition (%)

Element Content (%)
Chromium (Cr) 17.0–20.0
Nickel (Ni) 13.5–17.5
Molybdenum (Mo) 4.0–5.0
Nitrogen (N) 0.10–0.20
Manganese (Mn) ≤2.00
Phosphorus (P) ≤0.045
Sulfur (S) ≤0.030
Silicon (Si) ≤0.75
Carbon (C) ≤0.030
Iron (Fe) Balanced
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Mechanical properties (typical at 20°C)

Property Value
0.2% Yield Strength 205–245 MPa
Tensile Strength (UTS) 550–600 MPa
Elongation 40–53%
Rockwell B Hardness 80–96
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Physical properties

Property Value
Density 8.0 g/cm³ (0.290 lb/in³)
Modulus of Elasticity 200 GPa (29×10⁶ psi)
Melting Range 1393–1443°C
Specific Heat (0–100°C) 502 J/kg·K
Thermal Conductivity (100°C) 14.6 W/m·K
Electrical Resistivity (20°C) 85.1 μΩ·cm
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Key Features

• Excellent general and localized corrosion resistance, superior to 316L and 317L.
• High resistance to chloride pitting and crevice corrosion.
• Improved creep resistance due to nitrogen.
• Can be used without post-weld treatments.
• Non-magnetic in the annealed state.
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Available forms

• Bars
• Plates
• Sheets
• Tubes
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Industrial applications

Ideal for:
• Pollution Control: Flue Gas Desulfurization (FGD) systems.
• Chemical and Petrochemical Industry: Reactors, condensers, and heat exchangers.
• Food and Pharmaceutical Industry: Acid-resistant process equipment.
• Water Treatment: Tanks and filtration systems in the presence of chlorides.