Nickel Alloy 20 – Properties, Applications and Technical Data
Alloy 20 is an austenitic stainless steel alloy developed for very good corrosion resistance, especially in sulfuric acid and other aggressive chemical environments.
The alloy contains less than 50% iron and is alloyed with nickel, chromium and copper to improve resistance to acids, pitting corrosion and chloride attack.
Alloy 20 is widely used in the chemical process industry, petrochemical plants, power generation and the plastics industry where components are exposed to aggressive chemicals and corrosive environments.
Properties of Alloy 20
Alloy 20 is a nickel-iron-chromium alloy with additions of copper and molybdenum that provides very good corrosion resistance in sulfuric acid and other chemical process environments.
The alloy is often stabilized with niobium (columbium), which reduces the risk of carbide precipitation and improves resistance to intergranular corrosion.
- Type: austenitic nickel-based alloy
- Alloy: Ni-Fe-Cr-Cu-Mo
- Structure: austenitic alloy
- Designations: Alloy 20, Carpenter 20, UNS N08020, W.Nr. 2.4660, Alloy 20 Cb-3
- Typical composition: Ni ~32–38%, Cr ~19–21%, Cu ~3–4%, Mo ~2–3%
Advantages
- Excellent resistance to sulfuric acid
- Very good resistance to pitting corrosion
- Good resistance to chloride-induced stress corrosion cracking
- Stabilized structure through addition of niobium
- Good weldability and formability
Limitations
- Higher material cost than standard stainless steels
- Not optimal in very high temperature environments
- Can be more demanding to machine than standard steels
Common product forms for Alloy 20
- Round bar
- Sheet and strip
- Tubes and tubes
- Forgings
- Special dimensions according to drawing
Typical components manufactured in Alloy 20
- Heat exchangers
- Tanks and reactors
- Pipe systems
- Pumps and valves
- Equipment in the chemical process industry
Corrosion resistance
Alloy 20 offers very good corrosion resistance in sulfuric acid and in many oxidative and reducing chemical environments.
The alloy also has better resistance to pitting corrosion and chloride attack than 304 stainless steel and comparable performance to 316L in many environments.
Environments where Alloy 20 performs well
- Sulfuric acid applications
- Chemical process industry
- Petrochemical plants
- Power generation
Environments to avoid
- Very high temperatures where nickel-based superalloys are required
- Applications where simpler stainless steels are sufficient
Technical data
| Yield limit (0.2%) |
~310 MPa |
| Tensile strength |
~620 MPa |
| Elongation |
~35 % |
| Density |
~8.1 g/cm³ |
| Modulus of elasticity |
~195 GPa |
| Maximum working temperature |
~540 °C depending on application |
With a global network of suppliers, we can offer Alloy 20 in technical dimensions for demanding chemical and industrial applications.
Contact us for price, availability and technical advice.
Supplier of Alloy 20 with certified quality
HARALD PIHL is one of Europe's largest suppliers of special alloys, including corrosion-resistant nickel-based alloys such as Alloy 20.
With over 100 years of experience in the metal industry, we deliver materials with full traceability and certification according to EN 10204 3.1 / 3.2 as well as relevant ASTM and ISO standards.
Cutting, testing and quality assurance are carried out in-house to ensure the right tolerances and fast global delivery for technically demanding projects.
- Europe's largest stock of nickel and titanium alloys
- Special alloys from stock
- ASTM / ISO standards
- Top quality for safety-critical applications
- Fast global delivery
- Full material certification (EN 10204 3.1 / 3.2)
- Over 100 years in the metal industry
- Nickel and titanium experts
