UNS N10004 Forgings
Nickel molybdenum chromium superalloy, open die forged to customer drawing as rings, discs, shafts, sleeves and bars.
- UNS number
- N10004
- Trade name
- HASTELLOY® W
- Common name
- Alloy W
- Bar & forgings
- AMS 5755
- Filler wire
- AMS 5786
- AWS / ASME
- ERNiMo-3
- EN ISO 18274
- Ni 1004
- JIS
- YNiMo-3
Reviewed by the metallurgy team at Jiangyin Jiangnan Metal Co., Ltd. Last updated
UNS N10004 is a solid solution strengthened nickel molybdenum chromium superalloy. It contains 23 to 26 percent molybdenum, 4 to 6 percent chromium and 4 to 7 percent iron, with nickel as the balance. The alloy is sold under the trade name HASTELLOY® W and is also called Alloy W. Bar, rings and forgings in UNS N10004 are covered by SAE AMS 5755. Welding wire of the same chemistry is covered by AMS 5786 and classified ERNiMo-3 under AWS A5.14.
UNS N10004 was developed as a filler metal for joining dissimilar nickel and cobalt base alloys, and it is still specified for that work across the gas turbine and aerospace industries. In wrought form it is used for ring type parts in older gas turbine engines. The high molybdenum content gives good resistance to reducing media such as hydrochloric acid. The low chromium content limits the alloy in oxidising service above roughly 760 °C (1400 °F).
Jiangyin Jiangnan Metal Co., Ltd. open die forges UNS N10004 to customer drawings at its plant in Zhouzhuang Town, Jiangyin City, Jiangsu Province, China. Each order ships with an EN 10204 3.1 or 3.2 material certificate.
- Alloy family
- Nickel molybdenum chromium (Ni-Mo-Cr) superalloy
- Strengthening mechanism
- Solid solution. The alloy is not precipitation hardenable.
- Nominal composition
- Ni bal. / Mo 24% / Cr 5% / Fe 5.5%
- Density
- 9.03 g/cm³ (0.326 lb/in³)
- Melting range
- about 1300 to 1350 °C (2370 to 2460 °F)
- Heat treatment
- Solution anneal, then rapid quench. No ageing cycle.
- Useful strength to
- about 980 °C (1800 °F) in non oxidising service
- Oxidation limit
- Not recommended above about 760 °C (1400 °F) in oxidising atmospheres
- Modern substitute
- HAYNES® 242® alloy for ring applications
- Forged by
- Jiangyin Jiangnan Metal Co., Ltd., Jiangyin, Jiangsu, China
Chemical composition of UNS N10004
The table gives composition limits for UNS N10004 in weight percent. Jiangyin Jiangnan Metal checks the chemistry of every heat by optical emission spectrometry before forging, and reports the ladle analysis on the certificate.
| Element | Symbol | Composition (wt %) | Role in the alloy |
|---|---|---|---|
| Nickel | Ni | Balance (about 61) | Matrix, ductility and general corrosion resistance |
| Molybdenum | Mo | 23.0 to 26.0 | Solid solution strengthening, resistance to reducing acids |
| Iron | Fe | 4.0 to 7.0 | Hot workability and cost control |
| Chromium | Cr | 4.0 to 6.0 | Limited oxidation resistance |
| Manganese | Mn | 1.0 max | Deoxidiser, sulphur control |
| Silicon | Si | 1.0 max | Deoxidiser |
| Vanadium | V | 0.60 max | Residual from raw material |
| Carbon | C | 0.12 max | Held low to limit carbide precipitation |
| Phosphorus | P | 0.040 max | Restricted impurity |
| Sulphur | S | 0.030 max | Restricted impurity, harms hot workability |
Mechanical and physical properties
Typical room temperature properties for solution annealed UNS N10004 are listed below. These are indicative values published for general information. Acceptance values on an order are set by the applicable specification and the purchase order, and Jiangyin Jiangnan Metal tests to whichever one governs.
| Property | Metric | Imperial |
|---|---|---|
| Tensile strength | about 755 MPa | about 109,500 psi |
| Yield strength (0.2% offset) | about 360 MPa | about 52,000 psi |
| Elongation in 50 mm | about 42% | about 42% |
| Density | 9.03 g/cm³ | 0.326 lb/in³ |
| Melting range | 1300 to 1350 °C | 2370 to 2460 °F |
| Forging temperature | 1180 to 900 °C | 2155 to 1650 °F |
| Solution anneal | 1150 to 1175 °C, quench | 2100 to 2150 °F, quench |
| Maximum service, non oxidising | about 980 °C | about 1800 °F |
UNS N10004 forged product forms and size range
Jiangyin Jiangnan Metal forges the following product forms in UNS N10004. All parts are made to a customer drawing and are not held as catalogue stock, so intermediate sizes are available on request.
| Product form | Outside diameter or size | Length or height | Typical use |
|---|---|---|---|
| Seamless rolled rings | 150 to 2,500 mm OD | up to 800 mm | Turbine shroud rings, casing rings |
| Forged rings | 100 to 2,000 mm OD | up to 600 mm | Flange blanks, spacer rings |
| Forged discs and blanks | 100 to 1,500 mm OD | 20 to 400 mm thick | Valve seats, closure plates |
| Round bar | 30 to 800 mm dia. | up to 6,000 mm | Machining stock, stems, spindles |
| Forged shafts and spindles | 50 to 700 mm dia. | up to 6,000 mm | Pump and compressor shafts |
| Sleeves and bushings | 80 to 1,200 mm OD | up to 1,500 mm | Wear sleeves, bearing housings |
| Forged flanges | DN15 to DN1200 | ASME B16.5 / B16.47 or drawing | Piping connections |
| Tube sheets and plates | up to 2,500 mm | up to 400 mm thick | Heat exchanger tube sheets |
| Hollow forgings and cylinders | 150 to 1,500 mm OD | up to 3,000 mm | Pressure vessel sections |
How UNS N10004 forgings are manufactured
- Melting. The alloy is double melted, normally vacuum induction melting followed by electroslag or vacuum arc remelting, to control gas content and segregation.
- Homogenisation. Ingots are soaked to even out molybdenum segregation before any hot work starts.
- Cogging and open die forging. The billet is worked between 1180 °C and 900 °C. Working below 900 °C risks cracking, so the piece is reheated as often as the shape needs.
- Ring rolling. For ring geometries a pierced preform is expanded on a radial axial ring mill to give continuous circumferential grain flow.
- Solution annealing. Parts are held at 1150 to 1175 °C and rapidly quenched. UNS N10004 gains nothing from ageing, and a slow cool will precipitate carbides at grain boundaries.
- Rough machining. Scale is removed and test material is sampled from a prolongation of the forging.
- Testing and certification. Chemistry, mechanical tests and ultrasonic examination are completed, then the certificate is issued.
Testing, inspection and certification
Jiangyin Jiangnan Metal ultrasonically examines UNS N10004 forgings to EN 10228-3, SEP 1921 or ASTM A388, to whichever acceptance class the purchase order names. Material certificates are issued to EN 10204 3.1, or to EN 10204 3.2 with third party witness by an agency the customer nominates.
- Chemical analysis, ladle and on request product analysis
- Tensile and hardness testing from a forging prolongation
- Ultrasonic examination to EN 10228-3, SEP 1921 or ASTM A388
- Liquid penetrant examination to ASTM E165 where surface condition is critical
- Grain size and microstructure evaluation on request
- Dimensional report against the customer drawing
Where UNS N10004 forgings are used
Gas turbine and aerospace
Shroud rings, casing rings and rotor hub components in older gas turbine engines. The alloy is also the standard filler for combustor repair and for welding turbine blades to rotor hubs, so forged parts and wire are often ordered on the same project.
Dissimilar metal welded assemblies
Transition pieces joining cobalt base alloys such as HS-25 to iron nickel alloys such as A-286. Forged UNS N10004 inserts and rings keep the joint chemistry consistent with the filler.
Chemical process equipment
Valve bodies, seat rings, stems, pump shafts and sleeves handling hydrochloric acid and other reducing media, where the high molybdenum content does the work and oxidation resistance is not required.
Heat exchangers and pressure equipment
Tube sheets, forged flanges and nozzle forgings for shell and tube exchangers and pressure vessels running in reducing service.
UNS N10004 compared with related nickel alloys
Chromium content sets oxidation resistance and molybdenum content sets resistance to reducing acids. Those two numbers decide most selections between the grades below.
| Alloy | UNS | Ni | Mo | Cr | Chosen for |
|---|---|---|---|---|---|
| Alloy W | N10004 | bal. | 24 | 5 | Dissimilar metal welding, turbine rings |
| Hastelloy B-2 | N10665 | bal. | 28 | 1 max | Hydrochloric acid at all concentrations |
| Hastelloy B-3 | N10675 | bal. | 28.5 | 1.5 | B-2 service with better thermal stability |
| Hastelloy C-276 | N10276 | bal. | 16 | 16 | Mixed oxidising and reducing media |
| Hastelloy X | N06002 | 47 | 9 | 22 | High temperature oxidising strength |
| Haynes 242 | N10242 | bal. | 25 | 8 | Modern replacement for Alloy W rings |
Related grades forged by Jiangyin Jiangnan Metal: Hastelloy B-2 forgings, Hastelloy B-3 forgings, Hastelloy C-276 forgings, Hastelloy X forgings.
Frequently asked questions about UNS N10004
Is UNS N10004 the same as Hastelloy W?
Yes. UNS N10004 is the Unified Numbering System designation for the alloy sold commercially as HASTELLOY® W, also called Alloy W. The UNS number identifies the chemistry. The trade name identifies the producer's branded version of it.
Which standard covers UNS N10004 forgings?
SAE AMS 5755 covers UNS N10004 in bar, ring and forging form. AMS 5786 covers bar and welding wire, and AWS A5.14 classifies the same chemistry as ERNiMo-3 for bare filler metal. UNS N10004 is not listed in ASTM B564. That is a common misconception. ASTM B564 covers nickel alloy forgings but does not include this grade.
Can UNS N10004 be age hardened?
No. UNS N10004 is strengthened by solid solution, not by precipitation. The correct heat treatment is a solution anneal at 1150 to 1175 °C followed by a rapid quench. An ageing cycle gives no strength benefit and risks grain boundary carbide precipitation.
What is the maximum service temperature of UNS N10004?
UNS N10004 keeps useful mechanical properties to about 980 °C (1800 °F) in non oxidising conditions. In oxidising atmospheres the low chromium content limits it to roughly 760 °C (1400 °F), and long exposures beyond a few hundred hours above that temperature are not recommended.
What should replace UNS N10004 in a new design?
For ring type gas turbine components, HAYNES® 242® alloy (UNS N10242) is the modern substitute and gives better oxidation resistance and higher strength. UNS N10004 stays the correct choice when an existing engine drawing, repair procedure or weld specification calls for it by name.
What is the minimum order quantity for UNS N10004 forgings?
Jiangyin Jiangnan Metal forges UNS N10004 to order, so a single piece is acceptable when the drawing justifies it. The alloy is melted in heats rather than held in stock, so lead time and price depend on whether the required billet size can be drawn from an existing heat.
How do I request a quotation for a UNS N10004 forging?
Send the drawing or the finished dimensions, the quantity, the governing specification and the required certification level to sales@steelforgepieces.com, or call +86 189 2135 9659. Jiangyin Jiangnan Metal returns a quotation within 24 hours on working days.
UNS N10004 forging supplier
Jiangyin Jiangnan Metal Co., Ltd. is an open die forging factory in Jiangyin City, Jiangsu Province, China, producing nickel alloy, stainless steel, tool steel, alloy steel and carbon steel forgings to customer drawings. The company forges UNS N10004 rings, discs, shafts, sleeves, flanges and bars, and ships worldwide.
Jiangyin City, Jiangsu Province, China
References
- Haynes International, HASTELLOY® W alloy datasheet (UNS N10004)
- SAE International, AMS 5755, Nickel Alloy, Corrosion and Heat Resistant, Bars, Rings and Forgings
- SAE International, AMS 5786, Nickel Alloy Welding Wire
- AWS A5.14 / ASME SFA 5.14, Bare Nickel and Nickel Alloy Welding Electrodes and Rods, class ERNiMo-3
- BS EN ISO 18274, Welding consumables, designation Ni 1004 (NiMo25Cr5Fe5)
HASTELLOY® and HAYNES® are registered trademarks of Haynes International, Inc. Jiangyin Jiangnan Metal Co., Ltd. is not affiliated with, licensed by or endorsed by Haynes International, Inc. Trade names appear on this page only to identify the chemical composition a customer has specified. Property values are typical values published for general information. They are not guaranteed minimums and are not design data. Confirm acceptance values against the governing specification and your purchase order before design or purchase.