Seamless rolled rings
Ring rolled from a pierced and upset billet, giving continuous circumferential grain flow. Used for turbine casings, bearing races, flange rings and retaining rings.
OD 150 to 1500 mm, height to 400 mmUdimet 500 is a precipitation-hardenable nickel-chromium-cobalt superalloy (UNS N07500, W.Nr. 2.4983) strengthened by gamma-prime Ni3(Al,Ti) precipitation. It carries roughly 17 to 19 % chromium for oxidation and hot-corrosion resistance, together with cobalt, molybdenum and about 3 % each of aluminium and titanium. Service temperatures are typically 760 to 870 °C (1400 to 1600 °F).
Jiangyin Jiangnan Metal Co., Ltd. forges Udimet 500 to customer drawing as seamless rolled rings, flanges, round bars, discs, shafts, sleeves and valve components. Parts are supplied solution treated and aged to ASTM B637, AMS 5751 or AMS 5753, ultrasonically tested to EN 10228-3, SEP 1921 or ASTM A388, and certified to EN 10204 3.1 or 3.2.
What is Udimet 500?
Udimet 500 (UNS N07500) is one of the original wrought grades of the Udimet superalloy family, developed for gas turbine hot-section service.
Metallurgically, Udimet 500 sits in the nickel-chromium-cobalt group. Chromium at around 17 to 19 % forms the protective Cr2O3 scale that carries the alloy's oxidation and hot-corrosion resistance. Cobalt at 16 to 18 % and molybdenum at about 4 % strengthen the matrix in solid solution. The aluminium and titanium, roughly 3 % each, do the real work: together they precipitate the ordered gamma-prime phase Ni3(Al,Ti). Strength and creep life then follow from the volume fraction and size distribution of that phase, which heat treatment sets.
The combined aluminium plus titanium content is high, so Udimet 500 has a narrow hot-working window and work-hardens quickly. It is more demanding to forge and machine than a solid-solution alloy such as Inconel 625 or Hastelloy C-276. For that reason Udimet 500 forgings are normally produced from controlled-remelt billet, with close temperature management at every forging stage.
Equivalent designations and specifications
| System | Designation | Notes |
|---|---|---|
| UNS | N07500 | Primary North American designation |
| Werkstoff (W.Nr.) | 2.4983 | European material number |
| DIN | NiCr18CoMoAlTi | Descriptive German designation |
| AFNOR | NCK19DAT | French designation |
| SAE / AISI | 684 | Legacy US designation |
| ASTM | B637 | Precipitation-hardening nickel alloy bars, forgings and forging stock for high-temperature service |
| AMS | 5751, 5753 | Aerospace material specifications for bar, forgings and forging stock |
| Trade name | Udimet 500 | Also written Udimet-500 or Udimet500. UDIMET is a trademark of Special Metals Corporation |
| Designations are listed for cross-reference only. Confirm the exact governing specification and revision on your purchase order. Jiangyin Jiangnan Metal Co., Ltd. certifies against the specification stated on the order. | ||
Chemical composition of Udimet 500
Composition limits for Udimet 500 (UNS N07500) as given in ASTM B637, the specification most commonly used for forgings and forging stock.
| Element | Symbol | Composition limits, wt % | Typical mill analysis, wt % |
|---|---|---|---|
| Nickel | Ni | Remainder | ≈ 53 |
| Chromium | Cr | 15.00 to 20.00 | ≈ 17.5 |
| Cobalt | Co | 13.00 to 20.00 | ≈ 16.5 |
| Molybdenum | Mo | 3.00 to 5.00 | ≈ 4.0 |
| Titanium | Ti | 2.50 to 3.25 | ≈ 3.0 |
| Aluminium | Al | 2.50 to 3.25 | ≈ 2.9 |
| Iron | Fe | 4.00 max | ≈ 4.0 |
| Manganese | Mn | 0.75 max | < 0.10 |
| Silicon | Si | 0.75 max | < 0.15 |
| Carbon | C | 0.15 max | 0.05 to 0.10 |
| Copper | Cu | 0.15 max | < 0.05 |
| Boron | B | 0.003 to 0.010 | ≈ 0.006 |
| Phosphorus | P | 0.015 max | < 0.010 |
| Sulfur | S | 0.015 max | < 0.005 |
| Zirconium is often present at approximately 0.02 to 0.08 % as a grain-boundary strengthener where the purchase specification permits it. The actual heat analysis is reported on the EN 10204 3.1 certificate supplied with every Udimet 500 forging. | |||
Why the aluminium and titanium matter. Combined Al + Ti of about 6 % puts Udimet 500 well into the high-gamma-prime range. That is what buys the elevated-temperature strength. It is also what makes the alloy hard to hot-work, sensitive to strain rate, and prone to work-hardening during machining. Forging parameters have to be set accordingly.
Mechanical properties of Udimet 500 forgings
Room-temperature acceptance minima for Udimet 500 in the solution-treated and fully aged condition.
| Property | Metric | Imperial | Test method |
|---|---|---|---|
| Tensile strength, Rm | 1310 MPa min | 190 ksi min | ASTM E8 / ISO 6892-1 |
| Yield strength, Rp0.2 | 840 MPa min | 122 ksi min | ASTM E8 / ISO 6892-1 |
| Elongation, A | 20 % min | 20 % min | ASTM E8, 4D gauge |
| Reduction of area | To specification | To specification | ASTM E8 |
| Hardness | To specification | To specification | ASTM E18 (HRC) / E10 (HBW) |
| Stress-rupture | On request, to the purchase specification | ASTM E139 | |
| Values are acceptance minima, not design allowables. Elevated-temperature tensile, creep and stress-rupture testing can be added to the test plan when the purchase specification calls for it. | |||
Physical properties
| Property | Metric | Imperial |
|---|---|---|
| Density | 8.027 g/cm³ | 0.290 lb/in³ |
| Approximate melting point | ≈ 1360 °C | ≈ 2480 °F |
| Indicative maximum service temperature | 760 to 870 °C | 1400 to 1600 °F |
| Crystal structure | Austenitic FCC matrix with ordered L12 gamma-prime precipitate | |
| Magnetic response | Essentially non-magnetic in the solution-treated and aged condition | |
| Service temperature is indicative only and depends on stress, environment and required life. Take the design temperature from your own design code or stress analysis. | ||
Heat treatment of Udimet 500
Udimet 500 develops its properties through a solution treatment followed by a double age. Three-stage and four-stage cycles are both in use.
Figure 1. Udimet 500 three-stage heat treatment cycle (schematic)
Standard three-stage cycle
- Solution treat: 1080 °C (1975 °F), 4 hours, air cool
Dissolves the gamma-prime formed during forging and puts aluminium and titanium back into solution. Air cooling from solution temperature is deliberate. It starts the controlled re-precipitation of gamma-prime.
- Stabilisation age: 843 °C (1550 °F), 24 hours, air cool
Precipitates coarse primary gamma-prime and stabilises M23C6 carbides along the grain boundaries, which is what gives the alloy its creep-rupture ductility.
- Final age: 760 °C (1400 °F), 16 hours, air cool
Precipitates the fine secondary gamma-prime that carries peak room-temperature and intermediate-temperature strength.
Four-stage cycle
Where maximum creep-rupture life is required, a higher-temperature pre-solution step of approximately 1175 °C (2150 °F) for 2 hours is added ahead of the 1080 °C solution treatment. This coarsens the grain and improves creep resistance, at some cost in room-temperature tensile strength. That trade-off belongs to the design authority, not to the forge shop.
Furnace control. Every stage is time and temperature critical. Furnaces used for Udimet 500 should be surveyed and instrumented to AMS 2750 or an equivalent pyrometry standard, with charge thermocouples and a recorded chart for each load. Ask for the heat treatment chart to be included in your documentation package.
Udimet 500 compared with related superalloys
A quick orientation for buyers deciding between Udimet 500 and the alloys most often considered alongside it.
| Alloy | UNS | Base system | Strengthened by | Indicative max service temp. | Typical role |
|---|---|---|---|---|---|
| Udimet 500 | N07500 | Ni-Cr-Co | Gamma-prime, high Al+Ti | ≈ 870 °C | Turbine blades, hot-section rings and discs |
| Udimet 720 | N07720 | Ni-Cr-Co | Gamma-prime, very high volume fraction | ≈ 730 °C | High-strength turbine discs |
| Waspaloy | N07001 | Ni-Cr-Co | Gamma-prime, lower Al+Ti | ≈ 760 °C | Discs, shafts, casings, fasteners |
| René 41 | N07041 | Ni-Cr-Co | Gamma-prime | ≈ 870 °C | Rings, fasteners, hot sheet structure |
| Inconel 718 | N07718 | Ni-Cr-Fe | Gamma-double-prime, from niobium | ≈ 650 °C | Discs and casings. Most weldable of the group |
| Temperatures are broad orientation figures only and vary with stress, environment and required life. Superalloy grades are not interchangeable. Substitution requires the approval of the design authority. | |||||
Udimet 500 forged products we manufacture
Every Udimet 500 part is made to order from the customer's drawing or dimensions. There is no standard catalogue. The forms below are the ones we produce routinely.
Forged flanges
Weld-neck, slip-on, blind, long weld-neck, orifice and lap-joint patterns, or fully custom to drawing.
DN 15 to DN 900, to ASME B16.5 / B16.47 / EN 1092-1Round bars and forging stock
Forged and peeled or rough-turned bar for onward machining, supplied solution treated and aged or in the solution-treated condition.
Dia. 20 to 400 mm, length to 4000 mmDiscs and blanks
Upset-forged discs and pancake blanks with radial grain flow for hot-section rotating parts.
OD to 1200 mm, thickness 30 to 400 mmShafts and spindles
Drawn-down solid or trepanned shafts, stepped or plain, for pumps, compressors and drive trains.
Dia. 60 to 500 mm, length to 4000 mmSleeves, bushings and hollows
Pierced and mandrel-forged hollow sections for wear sleeves, liners and cylinder bodies.
OD to 800 mm, bore from 60 mmValve components
Valve bodies, bonnets, seat rings, stems, plugs and gate blocks for ball, gate, globe, check and plug valves.
Forged to drawing, rough or finish machinedTube sheets, nozzles and covers
Flat forged plate products and nozzle forgings for heat exchangers, reactors and pressure vessels.
To drawing, single-piece weight to 2000 kgOutside these ranges? Send the drawing anyway. Udimet 500 has a narrow hot-working window, so feasibility depends on the section transition and the number of reheats as much as on overall size. We will tell you whether a part is forgeable in this grade.
How Udimet 500 forgings are produced
The route below is the sequence Jiangyin Jiangnan Metal Co., Ltd. follows for Udimet 500 (UNS N07500) forgings.
- Melting and remelt
Udimet 500 billet is supplied double melted, by vacuum induction melting followed by electroslag remelting or vacuum arc remelting. The high aluminium and titanium content demands tight control of oxygen, nitrogen and non-metallic inclusions. The melting route is confirmed against your specification before the order is placed.
- Billet preparation and heating
Billet is conditioned, then soaked to the forging temperature on a controlled ramp. Soak time is set by section thickness so the core reaches temperature without overheating the surface.
- Open-die forging or ring rolling
Upsetting, drawing, piercing and mandrel work on the press, or piercing and rolling on the ring mill. Reduction is planned to close porosity and refine grain while keeping every pass inside the alloy's narrow hot-working window. Parts are returned to the furnace for reheat before temperature drops out of range.
- Heat treatment
Solution treatment plus double age per § 04, in surveyed furnaces with charge thermocouples and a recorded chart per load.
- Rough machining
Turning, boring and facing to the agreed machining allowance, or finish machining to drawing where required.
- Testing and inspection
Chemical analysis, mechanical testing, ultrasonic and surface NDT, dimensional inspection. See § 08.
- Marking, documentation and packing
Hard stamping or vibro-etch with heat number and part number, certificate package assembled, then packing in seaworthy cases for export.
Testing, inspection and certification
Udimet 500 forgings from Jiangyin Jiangnan Metal Co., Ltd. are released against a written test plan agreed before production starts.
| Test | Standard | Scope |
|---|---|---|
| Chemical analysis | ASTM E1473 / ASTM E1019 | Standard. Full heat analysis reported on certificate |
| Tensile testing | ASTM E8 / ISO 6892-1 | Standard. Room temperature; elevated temperature on request |
| Hardness | ASTM E18 / ASTM E10 | Standard |
| Ultrasonic testing | EN 10228-3 · SEP 1921 · ASTM A388 | Standard. Acceptance class to your order |
| Dye-penetrant testing | ASTM E165 / EN ISO 3452-1 | Optional |
| Grain size | ASTM E112 | Optional |
| Microstructure | ASTM E407 | Optional. Gamma-prime and carbide morphology |
| Positive material identification | Portable XRF / OES | Optional |
| Stress-rupture | ASTM E139 | Optional. To purchase specification |
| Dimensional report | To drawing | Standard |
Certification
- EN 10204 3.1. Mill certificate issued by our own independent quality department, supplied as standard with every order.
- EN 10204 3.2. Third-party certificate witnessed by an independent inspection body such as TÜV, BV, SGS, Lloyd's Register or DNV, available on request.
- Full traceability. Heat number carried from billet through forging, heat treatment, testing and marking.
Where Udimet 500 forgings are used
Udimet 500 is specified where a component must hold strength and dimensional stability in the 700 to 870 °C band, usually in an oxidising or hot-corrosive atmosphere.
- Gas turbines. Blades, vanes, hot-section rings, seal rings, casings and discs in aero and industrial engines.
- Power generation. Hot-gas-path components, combustion hardware, high-temperature fasteners and turbine rings.
- Oil, gas and petrochemical. High-temperature valve internals, seat rings, stems and bodies; reactor and furnace internals; wellhead components for hot service.
- Chemical process plant. Pump shafts, sleeves and impeller components handling hot corrosive media, plus process module internals.
- Aerospace and defence. Engine hardware and structural fasteners forged to AMS 5751 or AMS 5753.
- Heavy industry. Hot-working tooling, furnace rolls, extrusion and forging dies for elevated-temperature duty.
Machining and welding notes
Machining. Udimet 500 work-hardens rapidly and cuts with the gummy behaviour typical of gamma-prime superalloys, closer to Waspaloy than to stainless steel. Use rigid, heavy machines with minimum overhang, sharp positive-geometry tooling, a constant feed with no dwelling or rubbing, reduced surface speed and a generous coolant supply. Water-based coolant suits turning, milling and grinding. Heavy sulphurised or chlorinated lubricant suits drilling, boring, broaching and tapping. Remove all lubricant residue before high-temperature service, since sulphur and chlorine residues embrittle nickel alloys.
Welding. Gas-tungsten arc, gas metal-arc and shielded metal-arc welding are all used on Udimet 500. High Al+Ti gamma-prime alloys are sensitive to strain-age cracking, so joints normally need a full post-weld solution and re-age. Weld preparations must be clean and free of paint, marker, grease and oil. Discuss any welded fabrication with us and with your design authority before the forging is ordered.
Cold forming. Possible but limited by the alloy's high strength and rapid work-hardening. Use heavy-duty lubricants, soft die materials and generous radii and clearances, and expect short die life.
How to request a quotation
Send the items below to sales@steelforgepieces.com and you will normally have a quotation with weight, price and lead time within 24 hours.
- Drawing or dimensions. PDF, DWG or STEP, or the raw forging dimensions plus your machining allowance.
- Grade and specification. For example "Udimet 500 to ASTM B637" or "UNS N07500 to AMS 5751".
- Quantity. Piece count, and whether it is a one-off, a prototype or a repeat annual requirement.
- Delivery condition. As-forged, solution treated, solution treated and aged, rough machined or finish machined.
- NDT requirement. Ultrasonic standard and acceptance class, plus any surface NDT.
- Certificate level. EN 10204 3.1 or 3.2, and any witness or hold points.
- Destination and Incoterm. Port or door, EXW / FOB / CIF / DAP.
Udimet 500 frequently asked questions
What is Udimet 500?
Udimet 500 is a precipitation-hardenable nickel-chromium-cobalt superalloy, designated UNS N07500 and W.Nr. 2.4983. It contains roughly 17 to 19 % chromium, 16 to 18 % cobalt, 4 % molybdenum and about 3 % each of aluminium and titanium, with nickel as the balance. The aluminium and titanium form gamma-prime Ni3(Al,Ti) precipitates that give the alloy its high-temperature strength and creep resistance. The chromium provides oxidation and hot-corrosion resistance.
What is the UNS number, and are there other designations?
Udimet 500 is UNS N07500. It is also listed as W.Nr. / DIN 2.4983, DIN NiCr18CoMoAlTi, AFNOR NCK19DAT and AISI 684. The usual purchasing specifications are ASTM B637, AMS 5751 and AMS 5753. Jiangyin Jiangnan Metal Co., Ltd. supplies Udimet 500 forgings against any of these designations.
What is the chemical composition of Udimet 500?
Per ASTM B637 for UNS N07500: C 0.15 max, Mn 0.75 max, Si 0.75 max, P 0.015 max, S 0.015 max, Cr 15.00 to 20.00, Co 13.00 to 20.00, Mo 3.00 to 5.00, Ti 2.50 to 3.25, Al 2.50 to 3.25, B 0.003 to 0.010, Fe 4.00 max, Cu 0.15 max, Ni remainder. A typical mill analysis is about 53 % Ni, 17.5 % Cr, 16.5 % Co, 4 % Mo, 4 % Fe, 3 % Ti and 2.9 % Al. Full detail is in § 02.
What is the correct heat treatment for Udimet 500 forgings?
The standard three-stage treatment is: solution treat at 1080 °C (1975 °F) for 4 hours and air cool; stabilisation age at 843 °C (1550 °F) for 24 hours and air cool; final age at 760 °C (1400 °F) for 16 hours and air cool. A four-stage cycle adds a pre-solution step at about 1175 °C (2150 °F) for 2 hours where maximum creep-rupture life is needed.
What is the maximum service temperature of Udimet 500?
Udimet 500 is generally applied at metal temperatures up to roughly 760 to 870 °C (1400 to 1600 °F), depending on stress level and required life, and has a long history in gas turbine hot-section parts at the upper end of that band. The design temperature for a specific component must come from your own design code or stress analysis rather than from a general datasheet.
What mechanical properties can I expect?
Solution treated and aged, typical room-temperature acceptance minima are tensile strength 1310 MPa (190 ksi), 0.2 % yield strength 840 MPa (122 ksi) and elongation 20 %. Actual measured values for your heat are reported on the EN 10204 3.1 certificate.
Is Udimet 500 the same as Waspaloy or Inconel 718?
No. All three are nickel-base superalloys but they differ in strengthening mechanism and temperature capability. Udimet 500 (N07500) and Waspaloy (N07001) are both Ni-Cr-Co alloys strengthened by gamma-prime, and Udimet 500 carries more aluminium plus titanium, so it generally holds strength to a higher temperature. Inconel 718 (N07718) is a Ni-Cr-Fe alloy strengthened mainly by gamma-double-prime from niobium. It is far easier to weld and machine but is normally limited to about 650 °C. The grades are not interchangeable without the design authority's approval. See the comparison in § 05.
Can Udimet 500 be made as a seamless rolled ring, and in what sizes?
Yes. Udimet 500 is ductile enough to be open-die forged and ring rolled, though its narrow hot-working window means smaller sizes and more reheats than carbon or stainless steel. We produce Udimet 500 seamless rolled rings, flanges, bars, discs, shafts, sleeves and bushings to drawing. See § 06 for the size envelope. Send the drawing or the finished dimensions and quantity to sales@steelforgepieces.com for confirmation of feasibility and price.
How is Udimet 500 machined?
Udimet 500 work-hardens rapidly and has the gummy cutting behaviour typical of gamma-prime superalloys, so it is more demanding than stainless steel or Monel 400. Use rigid setups, sharp positive-geometry tooling, a constant feed with no dwelling or rubbing, reduced surface speed and generous coolant. Water-based coolant suits turning, milling and grinding. Heavy sulphurised lubricant suits drilling, boring, broaching and tapping. Remove all lubricant residue before high-temperature service to avoid embrittlement.
What testing and certification comes with the forgings?
Every order is supplied with an EN 10204 3.1 mill certificate covering chemical analysis and mechanical properties. EN 10204 3.2 third-party certification is available on request through TÜV, BV, SGS, Lloyd's Register or DNV. Ultrasonic testing is performed to EN 10228-3, SEP 1921 or ASTM A388 as specified, and dye-penetrant, hardness, grain size, microstructure, PMI and dimensional inspection can be added to the test plan. See § 08.
Who supplies Udimet 500 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, manufacturing Udimet 500 (UNS N07500) rings, flanges, bars, discs and shafts to customer drawing. Enquiries: sales@steelforgepieces.com or +86-189-2135-9659.
How do I request a quotation?
Send a drawing in PDF, DWG or STEP, or the raw dimensions with machining allowance, plus the grade and specification, quantity, delivery condition, NDT requirement and certificate level to sales@steelforgepieces.com. A quotation with weight, price and lead time is normally returned within 24 hours. The full checklist is in § 10.