What is 2.4608?
2.4608 is the Werkstoff (DIN/EN) material number for Alloy 333. The same alloy is designated NiCr26MoW in the EN system and UNS N06333 in the American system. It is a wrought nickel-chromium-iron alloy developed in the United States around 1950 as a lower-cost heat-resisting grade. The high iron content keeps the price down. The 24–26 % chromium builds a stable protective oxide. Molybdenum, cobalt and tungsten add solid-solution strength that holds above 1,000 °C.
What separates 2.4608 from cheaper heat-resisting grades is how it behaves under thermal cycling. About 1 % silicon works with the high chromium to resist carburisation and metal dusting. The alloy also takes repeated oil or water quenching without the scale spallation that limits leaner grades. Typical duty is therefore flare tips, radiant tubes, muffle furnaces, combustion chambers and gas turbine casings rather than steady-state service, where a cheaper alloy will do the job.
Where 2.4608 sits among heat-resisting alloys
Alloy 800H and the 300-series stainless steels sit below Alloy 333. They cost less but carburise faster and lose strength at lower temperatures. Haynes 230 and Inconel 617 sit above it, with more creep strength at 1,000 °C and a considerably higher price. 2.4608 falls between the two groups. It gives oxidation and carburisation resistance close to the higher grades at a cost nearer the iron-based ones.
2.4608 designations, equivalents and standards
2.4608, Alloy 333, UNS N06333 and NiCr26MoW all describe the same alloy. RA 333® is a registered trade name of Rolled Alloys for material of this composition. Jiangyin Jiangnan Metal supplies to the 2.4608 / N06333 chemistry and does not use that trade name.
| System | Designation | Notes |
|---|---|---|
| DIN / EN Werkstoff-Nr. | 2.4608 | Primary European material number |
| EN designation | NiCr26MoW | Nickel-chromium 26 with Mo and W |
| UNS | N06333 | Unified Numbering System, USA |
| Common name | Alloy 333 | Industry name used on enquiries and MTCs |
| Trade name | RA 333® | Rolled Alloys trademark for this composition |
| ASTM | B718, B719, B722, B723, B726 | Plate/sheet/strip, bar, seamless pipe & tube, welded pipe, welded tube |
| AMS | AMS 5593, AMS 5717 | Aerospace material specifications |
Chemical composition of 2.4608
2.4608 is specified as follows. The "typical" column is the mid-range aim chemistry Jiangyin Jiangnan Metal melts to for forging stock.
| Element | Symbol | Specified range | Typical aim |
|---|---|---|---|
| Nickel | Ni | 44.0–47.0 | 45 |
| Chromium | Cr | 24.0–26.0 | 25 |
| Iron | Fe | balance | ~18 |
| Molybdenum | Mo | 2.50–4.00 | 3 |
| Cobalt | Co | 2.50–4.00 | 3 |
| Tungsten | W | 2.50–4.00 | 3 |
| Manganese | Mn | ≤ 2.00 | 1.5 |
| Silicon | Si | 0.70–1.50 | 1.0 |
| Carbon | C | 0.03–0.08 | 0.05 |
| Copper | Cu | ≤ 0.50 | - |
| Phosphorus | P | ≤ 0.030 | - |
| Sulphur | S | ≤ 0.015 | - |
Silicon is held at 0.70–1.50 % on purpose rather than left as a residual. It is the main reason 2.4608 resists carburisation and metal dusting better than Alloy 800H.
Mechanical properties of 2.4608 from 21 °C to 1,204 °C
Strength falls off steadily as temperature rises. Typical annealed tensile data:
| Test temperature | Ultimate tensile strength | Elong. |
|---|---|---|
| 21 °C70 °F | 738 MPa · 107 ksi |
48 % |
| 871 °C1,600 °F | 190 MPa · 27.5 ksi |
75 % |
| 982 °C1,800 °F | 108 MPa · 15.7 ksi |
64 % |
| 1,093 °C2,000 °F | 51 MPa · 7.4 ksi |
25 % |
| 1,204 °C2,200 °F | 28 MPa · 4.0 ksi |
106 % |
Marker on each bar shows 0.2 % yield strength: 324, 165, 83, 45 and 24 MPa. Bar colour follows test temperature.
Minimum room-temperature properties, annealed
| Property | Minimum | Imperial |
|---|---|---|
| Tensile strength Rm | 550 MPa | 80 ksi |
| 0.2 % proof strength Rp0.2 | 240 MPa | 35 ksi |
| Elongation A5 | 30 % | 30 % |
| Modulus of elasticity | 201 GPa | 29.2 × 10&sup6; psi |
| Hardness, annealed | ~94 HRB | ~94 HRB |
Physical properties of 2.4608
| Property | Value (metric) | Value (imperial) |
|---|---|---|
| Density | 8.14 g/cm³ | 0.294 lb/in³ |
| Melting range | 1,245–1,300 °C | 2,273–2,372 °F |
| Thermal conductivity at 20 °C | 11.1 W/m·K | 6.4 Btu/hr·ft·°F |
| Specific heat capacity | 441 J/kg·K | 0.105 Btu/lb·°F |
| Electrical resistivity | 1.14 Ω·mm²/m | 114 µΩ·cm |
| Magnetic response | Non-magnetic in the annealed condition | |
Physical constants are typical published values for the annealed alloy. Values on your mill certificate govern for acceptance.
2.4608 forged product forms and size ranges
Jiangyin Jiangnan Metal Co., Ltd. forges 2.4608 to drawing rather than from a stock list. The ranges below cover the working envelope of the presses and the ring mill. Send a drawing and the achievable size will be confirmed on the quotation.
Seamless rolled rings
Radial-axial rolled from a punched, upset blank. Grain flow follows the circumference.
OD 200–4,000 mm · height to 1,000 mmForged rings
Press-forged and bored where the section is too heavy or the ratio too short to roll.
OD 100–3,000 mmForged flanges
Weld-neck, blind, slip-on and special profiles, forged and rough machined.
50–3,000 mmRound bars
Drawn under the press, straightened, peeled or turned as required.
Ø 20–1,200 mm · length to 12,000 mmDiscs and disks
Upset discs for valve seats, closures, blanks and turbine hardware.
Ø 100–2,500 mmShafts and spindles
Stepped shafts, eccentric shafts and spindles with full-length grain flow.
Ø 60–1,000 mmSleeves and bushings
Hollow forgings, trepanned or mandrel-forged to reduce machining loss.
OD 100–2,000 mmTube sheets
Heavy plate-form forgings for heat exchangers, ultrasonically tested before drilling.
to 3,000 mm · to 400 mm thickForged pipes and tubes
Hollow-forged and bored sections where seamless tube is not available in 2.4608.
OD 100–1,500 mmSingle-piece weight: 5 kg to 20,000 kg. Also produced in this alloy: valve bodies, valve stems, valve seat rings, nozzles, blocks, gears, crankshafts and bespoke open-die forged parts.
How Jiangyin Jiangnan Metal produces 2.4608 forgings
- Melting: EAF + VOD + ESR
Electric arc melting with vacuum oxygen decarburisation, then electroslag remelting. ESR controls sulphur, gas content and centreline segregation. Heavy 2.4608 sections tend to crack in forging without it.
- Open-die forging: 1,120–1,180 °C
Soak, then forge with a reduction ratio of at least 4:1 to break down the as-cast structure. Finishing stops above about 950 °C. The hot-working window is narrow and the alloy tears if it is worked below that.
- Ring rolling or profiling
Ring blanks are punched, upset and rolled on the radial-axial mill. Bars, shafts and discs are drawn or upset under the press to the rough-machining envelope.
- Solution anneal: 1,150–1,180 °C
Followed by rapid cooling to put carbides back into solution and restore oxidation resistance. Solution treatment and ageing can be run together where your specification calls for both.
- Rough machining
Turned or milled to your drawing with test-piece material and UT scanning surface left on.
- Testing and certification
Spectrographic chemistry, tensile, hardness, grain size and intergranular corrosion testing as specified. Ultrasonic testing to EN 10228-3, SEP 1921 or ASTM A388. Released with an EN 10204 3.1 mill certificate, or EN 10204 3.2 witnessed by TUV, BV, SGS or Lloyd's Register on request.
What 2.4608 forgings are used for
2.4608 is specified where a part cycles between high temperature and ambient, or where a carburising or sulphidising atmosphere would consume a leaner alloy. Typical forged applications:
| Industry | Forged components | Why 2.4608 |
|---|---|---|
| Oil & gas, refining | Flare tip rings and flanges, radiant tube supports, reformer hardware, forged tube sheets, forged flanges | Survives flame impingement and rain quench without scale spallation |
| Petrochemical & chemical | Muffle and retort components, columns, towers, preheater internals, crystalliser parts | Carburisation and metal-dusting resistance from 25 % Cr plus 1 % Si |
| Power generation | Combustion chamber rings, gas turbine casings, superheater and reheater headers | Solid-solution strength from Mo, Co and W above 1,000 °C |
| Heat treatment plant | Furnace rolls, retorts, fixtures, refractory anchors, muffle rings | Repeated heat-and-quench cycling without distortion or cracking |
| Valves & flow control | Valve bodies, stems, seat rings, blocks and closures for ball, gate, globe, check and plug valves | Hot strength plus machinable annealed condition |
| Rotating equipment | Seamless rolled rings, spindles, gears, compressor and gearbox parts | Circumferential grain flow from ring rolling |
| Marine & offshore | Subsea and deepwater production hardware, wellhead and Christmas tree components | Corrosion resistance combined with high-temperature capability |
2.4608 compared with Alloy 800H, 601, 617 and Haynes 230
2.4608 is often specified after Alloy 800H has proved too weak or carburised too quickly, and before the budget reaches Haynes 230. The table below sets out where each grade sits.
| Alloy | Ni % | Cr % | Key additions | Strength in the high range | Relative cost |
|---|---|---|---|---|---|
| 2.4608 / Alloy 333 | 45 | 25 | Mo 3, Co 3, W 3, Si 1 | Good; strong thermal-shock and carburisation resistance | Mid |
| Incoloy 800H | 32 | 21 | Al, Ti | Lower; carburises faster, cheapest route | Low |
| Inconel 601 | 61 | 23 | Al 1.4 | Excellent oxidation, less hot strength than 2.4608 | Mid |
| Inconel 617 | 54 | 22 | Co 12.5, Mo 9 | Higher creep strength above 1,000 °C | High |
| Haynes 230 | 57 | 22 | W 14, Mo 2 | Highest of this group; best long-term creep | High |
Composition figures are nominal and given for orientation. Alloy selection for a pressure or safety-critical part should be made against the applicable design code and the service atmosphere rather than from a summary table.
Machining, welding and handling notes
Machining
2.4608 work-hardens and machines like other solid-solution nickel alloys. Use a rigid setup, positive rake, sharp carbide tooling, a heavy constant feed and no dwelling. Take deep cuts at low surface speed rather than light cuts at high speed, since a light pass skims over the work-hardened layer and glazes it. Use flood coolant. Forgings are supplied rough machined so the finishing allowance is predictable.
Welding
Weld by GTAW, GMAW or SMAW with matching Alloy 333 filler. Keep heat input and interpass temperature low. Clean sulphur, lead, grease and marking paint off the joint before it sees heat, as these contaminants embrittle nickel alloys. Solution anneal after welding where the part will run in a carburising atmosphere or where restraint was high.
Hot working
Forge between 1,120 °C and 1,180 °C and stop above about 950 °C. Do not reheat and continue below that temperature. The alloy tears rather than flows once it drops out of its working range.
2.4608 frequently asked questions
What is material 2.4608?
2.4608 is the DIN/EN Werkstoff material number for Alloy 333, a nickel–chromium–iron superalloy containing roughly 45 % nickel, 25 % chromium and 18 % iron with additions of molybdenum, cobalt, tungsten and silicon. It is designated NiCr26MoW in EN and UNS N06333 in the American system, and is best known for resisting oxidation, carburisation and thermal shock above 1,000 °C.
What is 2.4608 equivalent to?
2.4608 is equivalent to UNS N06333, EN designation NiCr26MoW and the common industry name Alloy 333. It is the material number behind the RA 333® trade name. Product standards covering the composition include ASTM B718, B719, B722, B723 and B726, plus AMS 5593 and AMS 5717.
What is the chemical composition of 2.4608?
2.4608 contains 44.0–47.0 % nickel, 24.0–26.0 % chromium, 2.50–4.00 % molybdenum, 2.50–4.00 % cobalt, 2.50–4.00 % tungsten, 0.70–1.50 % silicon, up to 2.00 % manganese, 0.03–0.08 % carbon, up to 0.50 % copper, up to 0.030 % phosphorus and up to 0.015 % sulphur, with iron as the balance at roughly 18 %.
What is the maximum service temperature of 2.4608?
2.4608 retains useful strength above 1,000 °C and is normally applied continuously up to about 1,200 °C in oxidising atmospheres. Tensile strength falls from roughly 738 MPa at 21 °C to about 190 MPa at 871 °C and about 28 MPa at 1,204 °C, so design stress must be based on creep rather than room-temperature tensile data above roughly 650 °C.
Why choose 2.4608 instead of Alloy 800H or Alloy 601?
2.4608 carries about 45 % nickel against roughly 32 % in Alloy 800H, plus molybdenum, cobalt and tungsten for solid-solution strength and 1 % silicon for oxidation resistance. That combination resists carburisation and metal dusting better than Alloy 800H and holds more hot strength, and it takes thermal shock better than Alloy 601. Those properties suit flare tips, radiant tubes, muffles and gas turbine hardware that cycles between hot and cold.
Can 2.4608 be forged?
Yes. 2.4608 is a wrought alloy and is open-die forged in the 1,120–1,180 °C range with finishing above about 950 °C. Jiangyin Jiangnan Metal Co., Ltd. forges 2.4608 into seamless rolled rings, flanges, round bars, discs, shafts, sleeves, bushings and tube sheets, then solution anneals near 1,150–1,180 °C and cools rapidly.
What heat treatment does 2.4608 need after forging?
2.4608 forgings are solution annealed at approximately 1,150–1,180 °C and cooled rapidly. Ageing is applied only when a customer specification requires it. Jiangyin Jiangnan Metal Co., Ltd. can perform solution treatment and ageing together where the drawing calls for both.
Is 2.4608 weldable?
2.4608 is welded by GTAW, GMAW and SMAW using matching Alloy 333 filler. Keep heat input and interpass temperature low, clean the joint of sulphur- and lead-bearing contaminants before heating, and solution anneal after welding when the part will see carburising service or high restraint.
What sizes of 2.4608 forgings can you supply?
Jiangyin Jiangnan Metal Co., Ltd. forges 2.4608 rings from 200 mm to 4,000 mm outside diameter, round bars from 20 mm to 1,200 mm diameter, discs to 2,500 mm diameter and single pieces from 5 kg to 20,000 kg. Parts are forged to the customer drawing rather than to a stock list.
What certification comes with 2.4608 forgings?
Every 2.4608 forging is released with an EN 10204 3.1 mill test certificate covering heat number, chemistry, mechanical properties and heat-treatment records. EN 10204 3.2 certification witnessed by a third party such as TUV, BV, SGS or Lloyd's Register is available on request, as is ultrasonic testing to EN 10228-3, SEP 1921 or ASTM A388.
What is the density of 2.4608?
The density of 2.4608 (Alloy 333 / UNS N06333) is approximately 8.14 g/cm³, which is 0.294 lb/in³. Its melting range is roughly 1,245–1,300 °C and annealed hardness is about 94 HRB.
How do I get a price for a 2.4608 forging?
Send the drawing or the finished dimensions, the quantity, the required specification and any test or certification requirements to sales@steelforgepieces.com, or call +86-189-2135-9659. Jiangyin Jiangnan Metal Co., Ltd. is at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China, and quotes 2.4608 forgings to drawing.
Who forges this: Jiangyin Jiangnan Metal Co., Ltd.
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory in Jiangyin, Jiangsu Province, China. The works sits on the south bank of the Yangtze between Shanghai and Nanjing, in the centre of China's forging and special-steel industry. It forges carbon steel, alloy steel, tool steel, stainless steel and nickel-based superalloys including 2.4608 / Alloy 333, and ships to buyers in Europe, North America, the Middle East and Asia.
There is no stock list for 2.4608. Each ring, flange, shaft or disc is melted, forged, heat treated and certified against the order.
Contact the forging factory directly
Technical enquiries and drawings go straight to the works rather than to a trading desk.
Jiangyin Jiangnan Metal Co., Ltd.
- FactoryNo.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China
- Phone+86-189-2135-9659
- Emailsales@steelforgepieces.com
- Webwww.steelforgepieces.com
- LanguagesEnglish, Chinese
Put this in your 2.4608 RFQ
- Drawing, or finished OD × ID × height / length
- Quantity and required delivery date
- Specification and acceptance criteria (e.g. N06333 chemistry, tensile minima)
- Heat-treatment condition: solution annealed, or annealed and aged
- Machining state: as-forged, rough machined, or finish machined
- NDT class: UT to EN 10228-3, SEP 1921 or ASTM A388
- Certification: EN 10204 3.1, or 3.2 and which third party
Citing this page
The 2.4608 property data on this page is published for reference and may be quoted with attribution. Suggested citation:
Jiangyin Jiangnan Metal Co., Ltd. “2.4608 Forgings (Alloy 333 / UNS N06333): composition, properties and forged product forms.” steelforgepieces.com, Jiangyin, Jiangsu, China. Updated . https://www.steelforgepieces.com/Nickel-Alloy/2.4608.html
Reviewed by the technical sales team at Jiangyin Jiangnan Metal Co., Ltd., an open-die forging factory producing 2.4608 components. Composition and property ranges follow published DIN/EN and UNS data for material 2.4608 / N06333. The mill certificate supplied with each forging governs for acceptance.