---
title: "Hastelloy C-2000 / Alloy C-2000 Forgings (UNS N06200)"
description: "Hastelloy C-2000 and Alloy C-2000 forgings to ASTM B564: rolled rings, flanges, shafts, discs. UNS N06200, 23% Cr, 16% Mo, 1.6% Cu. China forging factory."
canonical: "https://www.steelforgepieces.com/Nickel-Alloy/Alloy-C-2000.html"
manufacturer: "Jiangyin Jiangnan Metal Co., Ltd."
address: "No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China"
telephone: "+86-189-2135-9659"
email: "sales@steelforgepieces.com"
date_published: "2019-03-12"
date_modified: "2026-08-15"
---

# Hastelloy C-2000 / Alloy C-2000 Forgings

**UNS N06200 · W.Nr. 2.4675 · NiCr23Mo16Cu · NS3405**

Forged rings, seamless rolled rings, flanges, shafts, discs, sleeves and tube sheets to
ASTM B564. Solution annealed, ultrasonically tested, certified to EN 10204 3.1 or 3.2.

**Hastelloy C-2000 and Alloy C-2000 are two names for the same nickel-chromium-molybdenum
alloy, specified as UNS N06200.** HASTELLOY® C-2000® is the Haynes International trade name;
Alloy C-2000 is the generic designation every other producer uses. The alloy contains nominally
23% chromium, 16% molybdenum and 1.6% copper, with nickel as the balance. The copper is what
makes it unusual. Most alloys in this family were developed to handle either oxidizing or
reducing conditions well and to tolerate the other. Copper and molybdenum together give
C-2000 real resistance to reducing acids such as sulfuric and hydrochloric, while 23%
chromium covers oxidizing media and streams carrying ferric ions or dissolved oxygen. One
grade holds both ends.

C-2000 is a single-phase, solid-solution alloy with no precipitation-hardening response, so
the only heat treatment applied is solution annealing at 1121 to 1149 °C followed by a rapid
water quench. Jiangyin Jiangnan Metal Co., Ltd. produces Hastelloy C-2000 and Alloy C-2000
open-die forgings to UNS N06200 at its plant in Zhouzhuang Town, Jiangyin City, Jiangsu Province, China, in sizes from 50 mm bar
up to 4000 mm rolled rings, with mill test certificates to EN 10204 3.1 or 3.2.

## Hastelloy C-2000 and Alloy C-2000: one alloy, two names

**HASTELLOY® C-2000® is the Haynes International trade name for this alloy. Alloy C-2000 is the
generic designation used by every other producer.** Both refer to the same nickel-chromium-
molybdenum-copper chemistry, specified internationally as UNS N06200 and W.Nr. 2.4675. Drawings
and enquiries use the two names interchangeably, and both are frequently written without the
hyphen, as Hastelloy C2000 or Alloy C2000.

| Designation | Origin |
|---|---|
| Hastelloy C-2000, Hastelloy C2000 | Registered trade name of Haynes International, Inc. |
| Alloy C-2000, Alloy C2000, C-2000 alloy | Generic industry designation |
| UNS N06200 | Unified Numbering System, USA |
| W.Nr. 2.4675 | German material number |
| NiCr23Mo16Cu | DIN designation |
| NS3405 | Chinese GB designation |
| Alloy 2000 | Shortened form used in parts of Europe |

### One distinction worth knowing before you order

UNS N06200 defines a composition range. Haynes holds its branded Hastelloy C-2000 to a tighter
internal window inside that range. Material from any other mill, including this one, is supplied
to the full UNS N06200 and ASTM B564 limits, which is what the great majority of project
specifications call for.

If your specification names Haynes-produced material specifically rather than the UNS number,
say so at enquiry stage. We will tell you plainly whether we can meet it rather than ship
against a specification we cannot satisfy.

## Key data at a glance

| Item | Value |
|---|---|
| Alloy designation | Alloy C-2000, also sold as Hastelloy® C-2000® alloy |
| UNS number | N06200 |
| Werkstoff number | 2.4675 |
| DIN designation | NiCr23Mo16Cu |
| GB (China) designation | NS3405 |
| Alloy family | Nickel-chromium-molybdenum-copper, solid-solution strengthened |
| Forging specification | ASTM B564 / ASME SB-564 |
| Related specifications | ASTM B574 (bar), B575 (plate), B366 (fittings), B619 / B622 / B626 (pipe & tube) |
| Supply condition | Solution annealed and water quenched |
| Density | 8.5 g/cm³ (0.307 lb/in³) |
| Melting range | 1328 to 1358 °C (2422 to 2476 °F) |
| Magnetic response | Non-magnetic, austenitic (µr approx. 1.002) |

## Chemical composition

Composition limits follow ASTM B564 for UNS N06200. Every heat is analyzed by optical
emission spectrometry and the certified analysis is supplied with the forging.

| Element | Symbol | Specified range (wt %) | Nominal |
|---|---|---|---|
| Nickel | Ni | Balance | 59 |
| Chromium | Cr | 22.0 to 24.0 | 23 |
| Molybdenum | Mo | 15.0 to 17.0 | 16 |
| **Copper** | **Cu** | **1.3 to 1.9** | **1.6** |
| Iron | Fe | 3.0 max | – |
| Cobalt | Co | 2.0 max | – |
| Manganese | Mn | 0.50 max | – |
| Aluminum | Al | 0.50 max | – |
| Silicon | Si | 0.08 max | – |
| Phosphorus | P | 0.025 max | – |
| Carbon | C | 0.010 max | – |
| Sulfur | S | 0.010 max | – |

Carbon is held to 0.010% maximum and silicon to 0.08% maximum. Both limits exist to suppress
grain-boundary precipitation during welding and slow cooling, which is why C-2000 holds its
corrosion resistance in the as-welded condition. It is also why melt practice matters more
for this grade than for a general-purpose stainless.

### Melting practice

Material is supplied from double-melted stock. The usual route is electric arc furnace with
argon-oxygen or vacuum-oxygen decarburization, followed by electroslag remelting
(EAF + AOD/VOD to ESR). Vacuum induction melting followed by ESR is used where a customer
specifies it. Double melting controls sulfur, oxygen and inclusion content, and gives the
ingot soundness that a forging of this section thickness needs.

## Mechanical properties

Room-temperature minimums per ASTM B564 for solution-annealed forgings. Typical mill results
run 10 to 15% above these figures.

| Property | Metric | Imperial | Basis |
|---|---|---|---|
| Tensile strength | 690 MPa min | 100 ksi min | ASTM B564 minimum |
| Yield strength (0.2% offset) | 310 MPa min | 45 ksi min | ASTM B564 minimum |
| Elongation in 4D | 45% min | 45% min | ASTM B564 minimum |
| Reduction of area | 50% typical | 50% typical | Not specified in B564, reported on request |
| Hardness | 87 to 92 HRB typical | 100 HRB max | Solution-annealed condition |
| Modulus of elasticity | 207 GPa approx. | 30 × 10⁶ psi approx. | Room temperature, typical |

Strength falls as temperature rises. Alloy C-2000 retains useful strength to roughly 649 °C,
but it is a wet-corrosion alloy rather than a high-temperature structural alloy.

## Forging and heat treatment

Hastelloy C-2000 has a narrow hot-working window and work hardens faster than austenitic
stainless steel. Most of the difficulty in forging it comes down to holding temperature.

| Operation | Temperature | Practice |
|---|---|---|
| Hot forging, start | 1232 °C (2250 °F) | Soak thoroughly so heat is uniform through section before the first blow |
| Hot forging, finish | 954 °C (1750 °F) min | Reheat rather than forge below this figure |
| Solution annealing | 1121 to 1149 °C (2050 to 2100 °F) | Hold 10 to 30 min depending on section, then rapid water quench |
| Age hardening | Not applicable | Solid-solution alloy with no precipitation-hardening response |
| Stress relief | Not normally applied | Intermediate-temperature holds risk secondary-phase precipitation |

### Why the finishing temperature matters

The window between 1232 °C and 954 °C is about 280 °C wide, roughly half what carbon steel
allows. A heavy ring rolled in a single heat will drop below 954 °C before the section is
reduced, so the piece goes back into the furnace between passes. Forging on below the finish
temperature does more than harden the part. It tears the grain structure, and the resulting
defects show up on ultrasonic inspection after annealing, by which point the material has
already been paid for.

### The anneal after forging

Every forging is re-annealed after the last hot working operation, and after any cold work
producing 7% or more outer-fiber elongation. Solution annealing dissolves the secondary
phases that form on slow cooling from forging heat. A part that skips it can still pass its
tensile test and then fail in service, because the mechanical properties are unaffected while
the corrosion resistance is not. Rapid water quench from annealing temperature is required.
Air cooling is acceptable only on sections under 10 mm.

## Forged product forms and sizes

| Product form | Size range | Typical application |
|---|---|---|
| Seamless rolled rings | OD 200 to 4000 mm | Vessel shell courses, bearing races, flange blanks |
| Forged rings | OD 150 to 2500 mm | Reactor closures, nozzle reinforcement |
| Forged flanges | DN 15 to DN 1200 | WN, SO, BL, LJ to ASME B16.5 / B16.47 / EN 1092-1 |
| Forged discs and tube sheets | Dia. up to 3000 mm | Shell-and-tube heat exchangers, blind covers |
| Forged bars and shafts | Dia. 50 to 1200 mm | Pump shafts, agitator shafts, valve stems |
| Forged sleeves and bushings | OD 100 to 1500 mm | Pump wear parts, mixer components |
| Forged blocks and valve bodies | Up to 10 t single piece | Valve bodies, manifolds, wellhead components |

All parts are made to drawing. Send the drawing or the finished dimensions with the machining
allowance you want, plus the specification, test requirements and certificate level.
Quotation follows within one working day.

## Hastelloy C-2000 compared with C-276, C-22 and Alloy 59

These four are the usual shortlist for aggressive acid service. They are not interchangeable.
The choice normally comes down to whether the process stream is oxidizing, reducing, or
swings between the two.

| Alloy | UNS | Cr % | Mo % | W % | Cu % | PREN* | Best suited to |
|---|---|---|---|---|---|---|---|
| **Hastelloy C-2000** | **N06200** | **23** | **16** | **–** | **1.6** | **76** | Both oxidizing and reducing acids, sulfuric acid service |
| Hastelloy C-276 | N10276 | 16 | 16 | 4 | – | 75 | Reducing conditions, long qualified service history |
| Hastelloy C-22 | N06022 | 22 | 13 | 3 | – | 70 | Oxidizing acids, mixed acid, FGD service |
| Alloy 59 | N06059 | 23 | 16 | – | – | 76 | High-purity Ni-Cr-Mo without the copper addition |

\* PREN calculated as Cr + 3.3 × (Mo + 0.5W) from the nominal composition, rounded to the
nearest whole number. PREN ranks pitting resistance in chloride media only. It says nothing
about behavior in sulfuric or hydrofluoric acid, where the copper in C-2000 is the deciding
factor. Confirm any selection against corrosion data for your actual medium, concentration
and temperature.

C-276 and C-22 were each developed toward one end of the oxidizing-reducing scale. C-2000 was
developed to hold both ends at once. That matters on plants running mixed acid, and where
feedstock changes move the stream composition around. It also matters where standardizing on
one alloy across a unit is worth more than a small gain on any single line.

## Applications for Hastelloy C-2000 forgings

**Chemical and petrochemical processing.** Reactor closures, forged nozzles, tube sheets and
shell-and-tube heat exchanger components in sulfuric acid, hydrochloric acid and mixed-acid
service. Rolled rings and forged flanges for columns, towers, tanks, silos and preheaters.

**Pumps, valves and rotating equipment.** Pump shafts, agitator and mixer shafts, plunger pump
components, valve bodies, valve stems, seat rings and blocks for ball, check, globe, gate and
plug valves handling corrosive media.

**Flue gas desulfurization and pollution control.** Forged rings and discs for scrubber
internals, absorber components and duct hardware, where chloride concentration and pH swing
over the operating cycle.

**Pharmaceutical and fine chemicals.** Forged components for crystallizers, reaction vessels
and process modules where product purity rules out iron contamination from the vessel wall.

**Oil, gas and offshore.** Forged bushings, sleeves, discs and manifold components for subsea
and deepwater production systems, wellhead and Christmas tree hardware, and sour-service
equipment carrying both H2S and chlorides.

## Testing, inspection and certification

- **Chemical analysis.** Optical emission spectrometry on every heat, certified analysis supplied with the forging.
- **Mechanical testing.** Tensile and hardness per ASTM B564 and ASTM A370, from test coupons heat treated with the production parts.
- **Ultrasonic testing.** To ASTM A388, EN 10228-3 or SEP 1921, acceptance class as specified on the order.
- **Liquid penetrant testing.** To ASTM E165 on machined surfaces where required.
- **Positive material identification.** Handheld XRF confirmation before dispatch.
- **Intergranular corrosion testing.** ASTM G28 Method A on request, to verify the solution anneal.
- **Dimensional inspection.** Full dimensional report against the customer drawing.
- **Material certificate.** EN 10204 3.1 as standard. EN 10204 3.2 counter-signed by TÜV, SGS, BV or Lloyd's Register on request.

Third-party inspection, witness testing and customer source inspection are welcome at the
plant. Certificate numbers and scope are available on request.

## Welding and machining

Hastelloy C-2000 welds readily by GTAW, GMAW and SMAW. Use matching filler: AWS A5.14 ERNiCrMo-17
wire, or AWS A5.11 ENiCrMo-17 covered electrodes. ERNiCrMo-10, the Alloy C-22 grade, is an
accepted substitute where matching filler is unavailable.

No preheat is required and post-weld heat treatment is not normally applied. Keep interpass
temperature low and heat input moderate. The low carbon and silicon limits are what allow the
alloy to hold its corrosion resistance as welded. For machining, the alloy work hardens
quickly, so use positive rake, rigid setups, slow speeds with heavy feeds, and never dwell in
the cut.

## Frequently asked questions

### What is Hastelloy C-2000 (Alloy C-2000)?

Alloy C-2000 (UNS N06200) is a nickel-chromium-molybdenum alloy containing nominally 23%
chromium, 16% molybdenum and 1.6% copper, with nickel as the balance. The copper is what makes
it unusual. Copper and molybdenum together give it resistance to reducing acids such as
sulfuric and hydrochloric, while the 23% chromium covers oxidizing media. It is a single-phase,
solid-solution alloy supplied in the solution-annealed condition.

### Is Hastelloy C-2000 the same as Alloy C-2000?

Yes, they are the same alloy. HASTELLOY C-2000 is the Haynes International trade name and Alloy
C-2000 is the generic designation used by other producers. Both are specified as UNS N06200 and
W.Nr. 2.4675, containing nominally 23% chromium, 16% molybdenum and 1.6% copper with nickel as
the balance. Both names are also written without the hyphen, as Hastelloy C2000 or Alloy C2000.
One distinction matters at order stage: UNS N06200 defines a composition range, and Haynes holds
its branded product to a tighter internal window inside that range. Forgings from other mills,
including Jiangyin Jiangnan Metal Co., Ltd., are supplied to the full UNS N06200 and ASTM B564
limits, which is what most project specifications require.

### What is the UNS number for Alloy C-2000?

The UNS number for Alloy C-2000 is N06200. Its German Werkstoff number is 2.4675, the DIN
designation is NiCr23Mo16Cu, and the Chinese GB designation is NS3405.

### Which standard covers Hastelloy C-2000 forgings?

Forgings and forged fittings in Alloy C-2000 are covered by ASTM B564, adopted as ASME SB-564.
Related product-form standards are ASTM B574 for rod and bar, ASTM B575 for plate, sheet and
strip, ASTM B366 for fittings, and ASTM B619, B622 and B626 for pipe and tube.

### Can Alloy C-2000 be hardened by heat treatment?

No. Alloy C-2000 is a solid-solution strengthened alloy with no precipitation-hardening
response, so it cannot be aged. The only heat treatment applied is solution annealing at
approximately 1121 to 1149 °C (2050 to 2100 °F) followed by a rapid water quench. That
treatment dissolves secondary phases and restores corrosion resistance and ductility. Strength
can be raised by cold work, but cold work reduces corrosion performance and is not used on
forged pressure parts.

### What is the forging temperature range for Hastelloy C-2000?

Hot forging starts at about 1232 °C (2250 °F) and must finish at or above 954 °C (1750 °F).
The working window is narrow compared with stainless steel, so the workpiece is reheated
between passes rather than forged down to a cold finish. Every forging is solution annealed
after the final hot working operation.

### What is the difference between Alloy C-2000 and Hastelloy C-276?

Both contain about 16% molybdenum. Alloy C-2000 carries 23% chromium and 1.6% copper with no
tungsten, while C-276 carries about 16% chromium and 4% tungsten with no copper addition. The
higher chromium gives C-2000 better resistance to oxidizing media and to streams contaminated
with ferric ions or dissolved oxygen, and the copper addition gives markedly better performance
in sulfuric acid. C-276 remains the choice where its service history is already qualified in an
existing plant.

### Is Alloy C-2000 magnetic?

No. Alloy C-2000 has an austenitic face-centered cubic structure and is non-magnetic in the
solution-annealed condition, with a relative magnetic permeability of approximately 1.002.

### Which filler metal is used to weld Hastelloy C-2000?

Matching filler is used: AWS A5.14 ERNiCrMo-17 wire for GTAW and GMAW, and AWS A5.11
ENiCrMo-17 covered electrodes for SMAW. Where matching filler is unavailable, ERNiCrMo-10, the
Alloy C-22 grade, is an accepted substitute. Keep interpass temperature low. No preheat or
post-weld heat treatment is normally required.

### Who manufactures Hastelloy C-2000 forgings in China?

Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory at No.1 Chengxiqiao Road,
Zhouzhuang Town, Jiangyin City, Jiangsu Province, China, producing Hastelloy C-2000 / Alloy C-2000 (UNS N06200)
forged rings, seamless rolled rings, flanges, shafts, discs, sleeves and tube sheets to
ASTM B564. Enquiries: sales@steelforgepieces.com, telephone +86-189-2135-9659.

### What material certificates are supplied?

Each heat is supplied with a mill test certificate to EN 10204 3.1 covering chemical analysis,
mechanical test results, heat treatment record, heat number and dimensional report. EN 10204
3.2 certification counter-signed by a third-party body such as TÜV, SGS, BV or Lloyd's Register
is available on request. Ultrasonic testing is carried out to ASTM A388, EN 10228-3 or SEP 1921
as specified.

### What sizes can be produced?

Seamless rolled rings from 200 mm to 4000 mm outside diameter, forged discs and tube sheets up
to 3000 mm diameter, forged bars and shafts from 50 mm to 1200 mm diameter, and single-piece
forged weights up to approximately 10 tonnes. Parts are made to drawing, so send the drawing or
the finished dimensions with your required machining allowance.

### What is the maximum service temperature?

Alloy C-2000 is a wet-corrosion alloy rather than a high-temperature alloy. It retains useful
strength to about 649 °C, but in aqueous acid service it is normally applied well below that,
and prolonged exposure in the intermediate temperature range can precipitate secondary phases
that reduce corrosion resistance. For sustained high-temperature structural duty, consider
Inconel 617, Inconel 601 or Incoloy 800HT instead.

## Manufacturer

**Jiangyin Jiangnan Metal Co., Ltd.** is an open-die forging factory in Jiangyin, Jiangsu
Province, China. The plant produces forged rings, seamless rolled rings, flanges, shafts,
discs, sleeves, bushings and tube sheets in carbon steel, alloy steel, tool steel, stainless
steel and nickel alloys, including Hastelloy C-2000 / Alloy C-2000 (UNS N06200), Hastelloy C-276, Hastelloy C-22,
Inconel 625 and Incoloy 825. All work is made to customer drawing and supplied with mill test
certificates to EN 10204 3.1 or 3.2.

| | |
|---|---|
| Company | Jiangyin Jiangnan Metal Co., Ltd. |
| Plant address | No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China |
| Telephone and WhatsApp | +86-189-2135-9659 |
| Email | sales@steelforgepieces.com |
| Website | https://www.steelforgepieces.com/ |

## Related nickel alloy forgings

- [Hastelloy C-276 (UNS N10276)](https://www.steelforgepieces.com/Nickel-Alloy/Hastelloy-C-276.html)
- [Hastelloy C-22 (UNS N06022)](https://www.steelforgepieces.com/Nickel-Alloy/Hastelloy-C-22.html)
- [Alloy 59 (UNS N06059)](https://www.steelforgepieces.com/Nickel-Alloy/Alloy-59.html)
- [Hastelloy C-4 (UNS N06455)](https://www.steelforgepieces.com/Nickel-Alloy/Hastelloy-C-4.html)
- [Hastelloy B-3 (UNS N10675)](https://www.steelforgepieces.com/Nickel-Alloy/Hastelloy-B-3.html)
- [Hastelloy G-3 (UNS N06985)](https://www.steelforgepieces.com/Nickel-Alloy/Hastelloy-G-3.html)
- [Inconel 625 (UNS N06625)](https://www.steelforgepieces.com/Nickel-Alloy/Inconel-625.html)
- [Incoloy 825 (UNS N08825)](https://www.steelforgepieces.com/Nickel-Alloy/Incoloy-825.html)
- [Alloy 602 (UNS N06025)](https://www.steelforgepieces.com/Nickel-Alloy/Alloy-602.html)
- [Inconel 617 (UNS N06617)](https://www.steelforgepieces.com/Nickel-Alloy/Inconel-617.html)

---

**Trademark notice.** HASTELLOY® and C-2000® are registered trademarks of Haynes
International, Inc. Jiangyin Jiangnan Metal Co., Ltd. is an independent forging manufacturer
and is not affiliated with, endorsed by or licensed by Haynes International. Those designations
appear here solely to identify the alloy chemistry. Forgings supplied by Jiangyin Jiangnan Metal
Co., Ltd. are manufactured to UNS N06200 and ASTM B564 and are not Haynes-produced material.

Technical data compiled from ASTM B564 and published alloy producer data, reviewed by the
Jiangyin Jiangnan Metal engineering department. Last reviewed: 15 August 2026. Data is given
for guidance. Confirm corrosion behavior against your own medium, concentration and temperature
before specifying.