Alloy 20 is a nickel-iron-chromium alloy engineered for corrosion resistance in harsh chemical processing environments. Its chemistry, including additions of copper, molybdenum, and niobium, provides strong resistance to sulfuric acid while helping protect against intergranular corrosion. Alloy 20 is often selected as a cost-effective alternative to higher nickel alloys when greater corrosion resistance is required than standard stainless steels can provide.
The alloy is widely used in chemical processing, petrochemical, pharmaceutical, food processing, and marine applications. Typical components include tanks, piping systems, heat exchangers, pumps, valves, fittings, and other equipment exposed to corrosive process media. Alloy 20 also offers good resistance to chloride stress corrosion cracking, pitting, and crevice corrosion, making it well suited for demanding service environments.
In addition to its corrosion performance, Alloy 20 can be readily formed, machined, and welded using conventional fabrication methods. Its combination of durability, fabrication versatility, and chemical resistance has made it a proven material for critical industrial applications where long-term reliability is essential.
Nickel Alloy 20 Chemical Composition
| Iron | Remainder | Niobium* + Tantalum | (8 x C) to 1.0 |
| Nickel | 32.0-38.0 | Silicon | 1.0 max |
| Chromium | 19.0-21.0 | Carbon | 0.07 max |
| Copper | 3.0-4.0 | Phosphorus | 0.045 max |
| Molybdenum | 2.0-3.0 | Sulfur | 0.035 max |
| Manganese | 2.0 max |
*Niobium (Nb) formerly classified as Columbium (Cb).
Nickel Alloy 20 Physical Properties
| Density, lb/in3 | 0.292 |
| Modulus of Elasticity, psi | 28.0 x 106 |
| Coefficient of Thermal Expansion, 68-212˚F, /˚F | 8.3 x 10-6 |
| Thermal Conductivity, Btu/ft hr ˚F | 6,7 |
| Specific Heat, Btu/lb ˚F | 0.109 |
| Electrical Resistivity, Microhm-in | 25.6 |
Nickel Alloy 20 Mechanical Properties
Mechanical property requirements for annealed bar product as specified in ASTM B160
| Yield Strength, min. (ksi) | 35 |
| Tensile Strength, min. (ksi) | 80 |
| Elongation, min. (%) | 30 |
Nickel Alloy 20 Standards
| ASTM B463, B464, B473, B366, B729 |
| ASME SB-463, SB-464, SB-473, SB-366, SB-729 |
Your Source for Nickel Alloy 20
At Double Eagle Alloys, we supply Nickel Alloy 20 in long bar, flanges, pipe/tube, and gaskets engineered for these demanding services. Contact our team to learn how Nickel Alloy 20 can support long-term performance and reliability.
Questions? We’d love to help. Contact us today to discuss your needs or to check current availability.
Contact Us
Data shown are typical and provided for informational purposes only. Values should not be considered minimums or maximums for specification or final design. Actual product data may vary, and information may be revised without notice.