Nickel Alloy · Open-Die Forgings
2.4660 Forgings — Alloy 20 / UNS N08020
Custom open-die forged rings, seamless rolled rings, flanges, bars, disks, shafts, sleeves and tube sheets in nickel-iron-chromium alloy 2.4660, forged to your drawing, ultrasonically tested, and supplied with EN 10204 3.1 or 3.2 certificates.
- 32-38%Nickel (Ni)
- 19-21%Chromium (Cr)
- 8.1Density g/cm3
- ≥551Tensile MPa (Rm)
What is 2.4660?
Jiangyin Jiangnan Metal is an open-die forging factory that produces 2.4660 forgings to the customer's size or drawing. The niobium (columbium) addition ties up carbon as niobium carbides, which prevents sensitization and the intergranular corrosion that can affect standard austenitic stainless steels in welded, high-temperature acid service. The copper content gives 2.4660 its resistance to sulfuric acid, while molybdenum and chromium provide general corrosion resistance.
2.4660 Forged Product Forms We Supply
We open-die forge and seamless-roll 2.4660 into the following shapes, in as-forged, rough-machined or finish-machined condition:
- Forged rings
- Seamless rolled rings
- Forged flanges
- Forged round bars
- Forged disks & discs
- Forged shafts & spindles
- Forged sleeves & bushings
- Forged tube sheets
- Forged tubes & pipes
- Forged gears & wheels
- Forged valve parts
- Forged nozzles & manifolds
2.4660 Equivalent Grades & Designations
2.4660 is known by several designations across standards bodies and mills, all referring to the same nickel-iron-chromium alloy:
| System / Body | Designation |
|---|---|
| Werkstoff (Germany) | 2.4660 |
| DIN name | NiCr20CuMo |
| UNS (USA) | N08020 |
| ASTM | 20Cb-3 |
| ISO | FeNi35Cr20Cu4Mo2 |
| Trade names | Alloy 20 · Carpenter 20 · Incoloy 20 · Nicrofer 3620 Nb |
Chemical Composition of 2.4660 (DIN 17744)
Jiangyin Jiangnan Metal supplies 2.4660 melted by AOD refining or vacuum induction melting, with vacuum-arc or electroslag remelting available. Composition per DIN 17744, in weight percent:
| C | Si | Mn | P | S | Cr | Mo | Ni | Cu | Nb | Co | Fe |
|---|---|---|---|---|---|---|---|---|---|---|---|
| ≤0.07 | ≤1.0 | ≤2.0 | ≤0.025 | ≤0.015 | 19.0-21.0 | 2.0-3.0 | 32.0-38.0 | 3.0-4.0 | 8×C - 1.0 | ≤1.5 | Bal. |
Mechanical Properties of 2.4660
Minimum room-temperature properties in the annealed (stabilized) condition:
| Tensile Rm (MPa) | Yield Rp0.2 (MPa) | Elongation A (%) | Reduction Z (%) | Condition |
|---|---|---|---|---|
| ≥551 | ≥241 | ≥30 | ≈50 | Forged & annealed |
Forging & Heat Treatment
Recommended thermal practice
Hot working: 1150-1230 °C (2100-2250 °F). Do not fall below 980 °C (1800 °F) before forging.
Annealing: 940-1010 °C (1725-1850 °F), hold at least 30 min per inch of thickness, then water quench.
Temperature control during hot working preserves the balanced chemistry and promotes formation of niobium carbides, so corrosion resistance is not impaired by sensitization. All 2.4660 forgings are solution-annealed after forging.
Why Choose 2.4660 / Alloy 20
2.4660 resists pitting and chloride-ion corrosion better than 304 stainless steel and on par with 316L, and is often selected to solve stress-corrosion-cracking problems that occur with 316L. Its copper content protects it from sulfuric acid, and it also resists phosphoric acid, organic acids, aqueous salt solutions and nitric acid. This makes it a lower-cost choice than higher-nickel alloys where strong acid resistance is required.
Applications of 2.4660 Forgings
Chemical & petrochemical
Reactor vessels, mixing tanks, process piping, bubble caps and heat exchangers.
Sulfuric & phosphoric acid
Pickling tanks, racks, heating coils, phosphate coating drums and acid-cleaning equipment.
Pharmaceutical & food
Processing of pharmaceuticals, plastics and organic and heavy chemicals.
Oil & gas
Oilfield and down-hole equipment, wellhead and Christmas-tree forged components.
Marine & offshore
Seawater pumps, ballast-system gate valves, deep-sea sampler and incubation chambers.
Power & equipment
Crystallizer equipment, synthetic-rubber plant, valve stems, seat rings and bodies.
Manufacturing, Testing & Certification
Every 2.4660 forging is produced in-house at our open-die forging factory and inspected before shipment. Standard quality package:
Send us the size or drawing of the 2.4660 forged part you need and we will quote our best price, with full material traceability from melt to finished forging.
About Jiangyin Jiangnan Metal Co., Ltd.
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory based in Jiangyin, Jiangsu Province, China. We forge rings, seamless rolled rings, flanges, bars, disks, shafts, sleeves and tube sheets in carbon steel, alloy steel, tool steel, stainless steel and nickel alloys, including 2.4660 / Alloy 20, and export worldwide with EN 10204 3.1 / 3.2 certification.
Frequently Asked Questions
What is material 2.4660?
What is the UNS equivalent of 2.4660?
What is 2.4660 / Alloy 20 used for?
Which 2.4660 forged products can you supply?
What certificates and testing come with 2.4660 forgings?
How should 2.4660 be forged and heat treated?
Need a 2.4660 forging quote?
Send us your size or drawing. We forge 2.4660 / Alloy 20 rings, flanges, bars and shafts to spec, certified and ultrasonically tested.