Materials · Incoloy
Alloy 20 fasteners
HAGUE FASTENERS makes Alloy 20 fasteners to order: bolts, studs, nuts and machined parts in Incoloy Alloy 20, also known as Carpenter 20 and 20Cb-3 (UNS N08020), made to your drawing in Willenhall for sulphuric acid and chemical service.
N08020
Also Carpenter 20 and 20Cb-3
32 to 38% Ni
Nickel with copper and molybdenum
620 MPa
Typical tensile strength
1 to 500
Prototypes to batches of several hundred
About the alloy
Made for sulphuric acid
HAGUE FASTENERS makes Alloy 20 fasteners in the UK for chemical plant. Alloy 20 has excellent corrosion resistance in chemical environments containing sulphuric acid, and useful resistance to environments containing chlorides, nitric acid and phosphoric acid.
It is used in the production of gasoline, solvents, explosives, inorganic and organic chemicals, pharmaceuticals, food and synthetic materials, and is readily made into mixing tanks, heat exchangers, process piping, pickling equipment, pumps, valves, fasteners and fittings. For harsher duty, see Incoloy 825 or Hastelloy.
At a glance
- Nickel-iron-chromium alloy with copper and molybdenum
- Excellent resistance to sulphuric acid
- Useful resistance to chlorides, nitric and phosphoric acids
- Niobium (columbium) stabilised
Composition
Alloy 20 chemical composition
Percentage by weight. Other elements: Fe balance.
| Element | Min % | Max % |
|---|---|---|
| Nickel (Ni) | 32.00 | 38.00 |
| Molybdenum (Mo) | 2.00 | 3.00 |
| Silicon (Si) | – | 1.00 |
| Chromium (Cr) | 19.00 | 21.00 |
| Carbon (C) | – | 0.07 |
| Nb (Cb) + Ta | 8 x C | 1.00 |
| Copper (Cu) | 3.00 | 4.00 |
| Manganese (Mn) | – | 2.00 |
| Sulphur (S) | – | .035 |
| Phosphorus (P) | – | .045 |
Properties
Mechanical properties (typical)
Typical values. Hardness on the Rockwell B scale.
| Property | Value |
|---|---|
| Tensile strength | 620 MPa |
| Yield strength (0.2% offset) | 300 MPa |
| Elongation in 2 in (50 mm) or 4D | 40% |
| Hardness | B83 |
This data is for general information only and may change without notice. HAGUE FASTENERS LIMITED believes it to be accurate but gives no warranty as to its accuracy or completeness and accepts no liability for its use. Actual properties may vary, and nothing here guarantees suitability for a particular use.
Equivalents and applications
Alloy 20 equivalents and typical uses
Alternative designations
Carpenter 20, 20Cb-3, Alloy 20, UNS N08020, ASTM B462, ASTM B472, ASTM B473, ASME SB472, ASME SB473, ISO 9723, ISO 9724, ISO 9725, DIN 17752 to 17754.
Typical applications
- Sulphuric acid plant
- Mixing tanks, heat exchangers and process piping
- Pickling equipment
- Pumps, valves and fittings
- Pharmaceutical, food and solvent production
What we make
Fasteners we make in Alloy 20
Certification and testing
Certified, traceable and tested
Bar comes from approved UK, EU or US mills, with heat numbers carried through to release. Testing is by independent UKAS-accredited laboratories, with EN 10204 3.1 or 3.2 certificates as required. See quality and testing.
- Mill certificates and heat traceability
- PMI and chemical analysis
- Solution annealing by approved partners, with furnace charts
- Laser-marked heat codes or part numbers
Questions
Frequently asked questions
What is the equivalent of Alloy 20?
Alloy 20 is UNS N08020, also known as Carpenter 20 and 20Cb-3. Bar is supplied to ASTM B473.
Is Carpenter 20 the same as Incoloy Alloy 20?
Yes. They are trade names for the same UNS N08020 alloy.
What are Alloy 20 fasteners used for?
Alloy 20 fasteners are used mainly in sulphuric acid service and in chemical, pharmaceutical and food plant where stainless steel would corrode.
Can you make Alloy 20 bolts in small batches?
Yes. We make single prototypes and breakdown replacements as well as batches of several hundred.
Alloy 20 enquiry?
Send us your drawing or specification
Tell us the sizes, quantity and documentation you need, and we will reply quickly.