Chemical composition
Nominal: mid-range where both limits are given, the cap where only a maximum is, balance takes the remainder. Exact specified ranges below.
| Element | Name | Content % | |
|---|---|---|---|
| Main elements5 elements | |||
| Ni | Nickel | 32 – 38% | |
| Fe | Iron | Bal. | |
| Cr | Chromium | 19 – 21% | |
| Cu | Copper | 3 – 4% | |
| Mo | Molybdenum | 2 – 3% | |
| Element | Name | Content % | |
|---|---|---|---|
| Minor & residual6 elements | |||
| Nb+Ta | Niobium + tantalum | ≥ 8 × C , ≤ 1% | |
| C | Carbon | ≤ 0.07% | |
| Mn | Manganese | ≤ 2% | |
| Si | Silicon | ≤ 1% | |
| P | Phosphorus | ≤ 0.045% | |
| S | Sulphur | ≤ 0.035% | |
Mechanical minima by form
Guaranteed values differ by form, size and delivery condition; quotations confirm the specification, form, size and condition.
| Form | Condition | Rm MPa | Rp0.2 MPa | A ≥ % | Other requirements and notes |
|---|---|---|---|---|---|
| Bar and forgings | |||||
| Hot- or cold-worked bar | Stabilise annealed (recommended 927–1010 °C, water quenched or otherwise rapidly cooled) | ≥ 551 (80 ksi) | ≥ 241 (35 ksi) | ≥ 30 | |
| Round bar | Strain hardened after stabilise annealing, dia. 50.8 mm and under | ≥ 620 (90 ksi) | ≥ 415 (60 ksi) | ≥ 15 | |
| Forgings, flanges, fittings and valve parts | Stabilise annealed | ≥ 551 (80 ksi) | ≥ 241 (35 ksi) | ≥ 30 | |
| Bars and shapes (boiler and pressure-vessel use) | Stabilized-annealed, size ≤50.8 mm | ≥ 550 (80 ksi) | ≥ 240 (35 ksi) | ≥ 30 | Also specified: Reduction of area Z ≥ 50 % |
| Plate, sheet and strip | |||||
| Plate, sheet and strip | Stabilise annealed (recommended 982-1010 °C) | ≥ 551 (80 ksi) | ≥ 241 (35 ksi) | ≥ 30 | Also specified: Hardness ≤ 217 HB (95 HRB) |
| Tube and pipe | |||||
| Automatic fusion-welded pipe | Stabilise annealed (recommended 982-1010 °C) | ≥ 551 (80 ksi) | ≥ 241 (35 ksi) | ≥ 30 | |
| Seamless pipe and tube | Stabilise annealed (recommended 982-1010 °C) | ≥ 550 (80 ksi) | ≥ 240 (35 ksi) | ≥ 30 | |
| Fittings and flanges | |||||
| Fittings (factory-made wrought butt-weld / socket) | 1700-1850 °F [927-1010 °C], rapid air or water quench | — | — | — | Recommended temperature; tolerance ±15 °C (±25 °F). Tensile properties follow the starting material. No tension test on the finished fitting unless agreed. |
| Fittings (wrought austenitic stainless, butt-weld / socket) | Solution annealed 1700–1850 °F [927–1010 °C], water quenched or otherwise rapidly cooled | ≥ 550 (80 ksi) | ≥ 240 (35 ksi) | ≥ 28 | Elongation: ≥28% longitudinal, ≥20% transverse. A single temperature is a minimum. All fittings are supplied heat-treated. |
| Wire and filler metals | |||||
| Wire | Stabilise annealed | 620 – 830 | — | — | |
Where this grade is recommended
Matched in 3 service conditions; ranks and scores computed from the condition-scoring matrix.
| Service condition | Industry | Temperature | Rank | Score |
|---|---|---|---|---|
| Sulphuric acid | Chemical Processing | ≤ 80 °C | 1 / 8 | 95 |
| Phosphoric acid | Chemical Processing | ≤ 80 °C | 2 / 7 | 88 |
| Amine sweetening & acid gas | Oil & Gas | ≤ 60 °C | 3 / 5 | 86 |
Designations & equivalents
| W.Nr. (Germany) | 2.4660 |
| EN designation | NiCr20CuMo |
| Trade name(s) | Alloy 20 / Carpenter 20Cb-3 / Nicrofer 3620Nb |
| ASTM / AISI | A182 / A240 / A276 / A403 / A479 / A480 / A484 / B366 / B462 / B463 / B464 / B468 / B471 / B472 / B473 / B474 / B475 / B729 / B751 / B775 / B829 / B906 |
Cross-references are common near-equivalents for search and shortlisting; substitution across standards requires clause-by-clause verification. All grades in one cross-reference table →
Applicable standards
9 specifications. Name the standard and its edition on the order.
Guaranteed values and required tests differ between specifications — see Mechanical minima by form for the figures per form.
Frequently asked questions
What is Alloy 20 (Alloy 020) · UNS N08020?
Alloy 20 (Alloy 020) · UNS N08020 — Ni corrosion-resistant. Dedicated sulphuric-acid grade — valves, pumps and heat exchangers
What is the maximum service temperature of N08020?
Typically about 425 °C; the practical limit depends on media, stress and design life — acceptance per the governing standard.
What is the tensile strength of N08020?
The specified minimum tensile strength is 551 MPa for the main product form. Minima for other forms and sizes are listed under "Mechanical minima by form" on this page.
Which standards cover N08020?
ASTM B463, ASTM B473, ASTM B464/B464M, ASTM B729, ASTM B468, ASTM B462, ASTM B366, ASTM A240/A240M, ASTM A182/A182M
Where is N08020 typically used?
Sulphuric acid (Chemical Processing); Phosphoric acid (Chemical Processing); Amine sweetening & acid gas (Oil & Gas)
In which forms is N08020 available?
Tube, plate, strip, bar, forgings, wire and other forms — sizes and delivery condition confirmed per order, with EN 10204 3.1 / 3.2 certification.
Same series
Download PDF datasheet
This grade’s datasheet as an A4 PDF — for filing, printing or forwarding to colleagues.
Download PDF datasheetSupply & enquiry
Tube & pipeφ1 – 219 × 0.25 – 25 mm
Plate4.76 – 80 mm
Barφ8 – 300 mm
Wire & filler metalsφ0.01 – 8 mmFor this grade we can supply, against your service conditions:
- Tube, plate, strip, bar, forgings, wire and more — with size range and lead time
- Chemistry and mechanical test report (EN 10204 3.1 / 3.2)
- Like-for-like alternatives and selection advice
- Applicable standards and inspection scope
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