Jiangyin Jiangnan Metal Co., Ltd.Open-die forging factory, Jiangyin, Jiangsu, China
UNS N06625 / W.Nr. 2.4856
Bellows quality, low cycle fatigue alloy 625, forged to ASTM B564 by Jiangyin Jiangnan Metal Co., Ltd., an open-die forging factory in Jiangyin, Jiangsu, China.
Alloy 625LCF is a low cycle fatigue, bellows quality version of nickel chromium molybdenum alloy 625 (UNS N06625, W.Nr. 2.4856). LCF stands for low cycle fatigue. The grade is made to tighter limits on carbon (0.03 % max), silicon (0.15 % max) and nitrogen (0.02 % max) than standard alloy 625, with controlled inclusion content and a fine, uniform grain size. It therefore lasts longer under repeated flexing at temperature while keeping the seawater, chloride and acid resistance of alloy 625.
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China. We forge Alloy 625LCF to ASTM B564 as seamless rolled rings, flanges, round bars, discs, sleeves, bushings, tube sheets, shafts and nozzles. Material is melted by EAF, VOD and ESR, and supplied with EN 10204 3.1 or 3.2 certificates. For a quotation, email sales@steelforgepieces.com or call +86-189-2135-9659.
Alloy 625 is a nickel chromium molybdenum alloy with niobium, used for its resistance to seawater, chlorides, phosphoric acid and sour service. Alloy 625LCF carries the same UNS number, N06625, and the same base chemistry, so its corrosion behaviour is the same. The difference is cleanliness and grain size.
Carbon is held to 0.03 % instead of 0.10 %, silicon to 0.15 % instead of 0.50 %, and nitrogen is capped at 0.02 %. The result is fewer carbide and nitride stringers, which are the sites where fatigue cracks tend to start. In a part that flexes in service, such as a bellows convolution or an expansion joint, fatigue rather than corrosion usually sets the life of the part, so the cleaner grade lasts longer.
| Attribute | Alloy 625 (standard) | Alloy 625LCF |
|---|---|---|
| UNS number | N06625 | N06625 |
| Carbon, wt % | 0.10 max | 0.03 max |
| Silicon, wt % | 0.50 max | 0.15 max |
| Nitrogen, wt % | not specified | 0.02 max |
| Grain size | not restricted | fine and uniform, controlled |
| Main design driver | corrosion resistance and strength | low cycle fatigue life and formability |
| Typical use | piping, vessels, seawater hardware, cladding | bellows, expansion joints, flexible couplings, cyclic service forgings |
The table below is the specification we work to for Alloy 625LCF forgings. The actual analysis of each heat is reported on the mill certificate.
| Element | Symbol | Specification, wt % |
|---|---|---|
| Nickel | Ni | 58.0 min |
| Chromium | Cr | 20.0 to 23.0 |
| Molybdenum | Mo | 8.0 to 10.0 |
| Niobium plus tantalum | Nb + Ta | 3.15 to 4.15 |
| Iron | Fe | 5.0 max |
| Cobalt | Co | 1.0 max |
| Manganese | Mn | 0.50 max |
| Aluminium | Al | 0.40 max |
| Titanium | Ti | 0.40 max |
| Silicon | Si | 0.15 max |
| Carbon | C | 0.03 max |
| Nitrogen | N | 0.02 max |
| Phosphorus | P | 0.015 max |
| Sulphur | S | 0.015 max |
Nickel is reported including cobalt.
Typical room temperature values for Alloy 625LCF in the solution annealed condition. Acceptance values for an order are those stated in the applicable specification and on the purchase order.
| Property | Metric | Imperial |
|---|---|---|
| Tensile strength | 769.5 MPa | 111.6 ksi |
| Yield strength, 0.2 % offset | 319 MPa | 46.3 ksi |
| Elongation at break | 63 % | 63 % |
| Elastic modulus | 208 GPa | 30.2 × 10³ ksi |
| Shear modulus | 81.4 GPa | 11.8 × 10³ ksi |
| Poisson's ratio | 0.28 | 0.28 |
| Hardness | 84 HRB | 84 HRB |
| Property | Value |
|---|---|
| Density | 8.44 g/cm³ (0.305 lb/in³) |
| Melting range | 1290 to 1350 °C (2350 to 2460 °F) |
| Specific heat, 20 °C | 410 J/kg·K |
| Thermal conductivity, 20 °C | 9.8 W/m·K |
| Electrical resistivity, 20 °C | 1.29 µΩ·m |
| Mean coefficient of expansion, 20 to 100 °C | 12.8 µm/m·°C |
| Magnetic permeability | about 1.0006, non magnetic |
Open-die forging needs no part specific tooling, so a single prototype piece is as practical as a production batch. We supply Alloy 625LCF in the following forms, as forged or machined to drawing.
| Forged form | Size range | Typical application |
|---|---|---|
| Seamless rolled rings | OD 200 to 2500 mm, height to 800 mm | Bellows end rings, flange blanks, bearing races |
| Forged rings and retaining rings | OD 100 to 2500 mm | Vessel and valve components |
| Flanges, WN, SO, blind, hubs | DN 15 to DN 1200 | Piping, heat exchangers, subsea connectors |
| Round bars and shafts | Dia. 20 to 800 mm, length to 6000 mm | Pump shafts, spindles, valve stems |
| Discs and disks | Dia. 100 to 2000 mm | Turbine and compressor parts, blanks |
| Sleeves and bushings | OD 80 to 1500 mm | Wear parts, subsea hardware |
| Tube sheets and forged plate | Dia. to 2500 mm, thickness to 400 mm | Shell and tube heat exchangers |
| Hollow bars, forged tubes and pipes | OD 100 to 1200 mm | Pressure parts, nozzles |
| Nozzles, blocks, valve bodies | To customer drawing | Valves, wellhead and Christmas tree parts |
Sizes outside this range are quoted case by case. Send the drawing and we will confirm feasibility before quoting.
Every step below is recorded and appears on the material certificate.
| Item | Standard or detail |
|---|---|
| Ultrasonic testing | EN 10228-3, SEP 1921, ASTM A388. Acceptance class agreed at order |
| Chemical analysis | Ladle and product analysis, reported per heat |
| Mechanical testing | Tensile, elongation, reduction of area, hardness |
| Impact testing | Charpy V notch, room or low temperature, on request |
| Surface NDT | Dye penetrant testing on request |
| Material certificate | EN 10204 3.1, or 3.2 witnessed by TUV, SGS, BV or Lloyd's Register |
| Grain size and microstructure | Reported on request |
| PMI | Positive material identification on request |
| Industry | Typical Alloy 625LCF forgings |
|---|---|
| Bellows and expansion joints | End rings, sleeves, weld collars, flexible coupling parts |
| Offshore and subsea oil and gas | Bushings, sleeves, discs, wellhead and Christmas tree components, hubs for deepwater production systems |
| Chemical processing | Shafts for chemical and plunger pumps, rolled rings, nozzles, crystalliser parts |
| Pressure vessels and heat exchangers | Tube sheets, flanges, forged tubes and pipes, shafts for air receivers and shell and tube exchangers |
| Columns, towers, tanks and silos | Flanges, rings, pipes, preheater and process module components |
| Valves | Valve stems, seat rings, blocks and bodies for ball, check, globe, gate and plug valves |
| Power transmission and rotating equipment | Rings, spindles, bars and gears for turbines, gas compressors and gearboxes |
| Heavy machinery and mills | Forged crankshafts, eccentric shafts, rolls and nozzles for cement, sugar and concrete mills |
| Marine, pulp and paper, pharmaceutical | Forged wheels, manifolds, rolls, shipbuilding and biochemistry equipment parts |
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China, in the Yangtze River Delta forging cluster, around two hours from Shanghai port. We forge carbon steel, alloy steel, tool steel, stainless steel and nickel alloys, and supply rings, seamless rolled rings, flanges, bars, discs, sleeves, tube sheets and shafts to pressure vessel, valve, oil and gas, power and heavy machinery manufacturers worldwide.
Address: No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China
Phone: +86-189-2135-9659
Email: sales@steelforgepieces.com
Send the drawing, or simply the dimensions, to sales@steelforgepieces.com. A quotation comes back faster when the enquiry includes:
We quote Alloy 625LCF open-die forgings and seamless rolled rings against drawings or dimensions, worldwide, with EN 10204 3.1 or 3.2 certificates.
Jiangyin Jiangnan Metal Co., Ltd.
Open-Die Forging Factory
Address: No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China
Phone: +86-189-2135-9659
Email: sales@steelforgepieces.com
Alloy 625LCF is a low cycle fatigue, bellows quality version of nickel chromium molybdenum alloy 625 (UNS N06625, W.Nr. 2.4856). LCF stands for low cycle fatigue. It is made to tighter limits on carbon (0.03 % max), silicon (0.15 % max) and nitrogen (0.02 % max) than standard alloy 625, with controlled inclusion content and a fine, uniform grain size, so it lasts longer under repeated flexing at temperature.
Both grades carry the UNS number N06625 and the same base chemistry, so corrosion resistance is the same. The difference is cleanliness and grain size. Alloy 625LCF holds carbon to 0.03 % max instead of 0.10 % max, silicon to 0.15 % max instead of 0.50 % max, and adds a nitrogen limit of 0.02 % max. Fewer carbide and nitride stringers and a finer grain size raise low cycle fatigue life and allow forming into thin bellows convolutions.
We supply Alloy 625LCF forgings to ASTM B564, the specification for nickel alloy forgings covering UNS N06625. Related specifications for other product forms are ASTM B443 for plate, sheet and strip, and ASTM B446 for rod and bar. Certification is to EN 10204 3.1, or 3.2 with third party witness.
Seamless rolled rings, forged rings, flanges, round bars, discs and disks, sleeves, bushings, tube sheets, shafts, spindles, nozzles, hollow bars, forged tubes and pipes, valve bodies and seat rings, and open-die profiles made to the customer drawing.
We melt Alloy 625LCF by the EAF, VOD and ESR route, which keeps sulphur, phosphorus and non metallic inclusions low. Forgings are normally supplied solution annealed. Solution treatment plus ageing is applied when the customer specification calls for it, and the condition is recorded on the material certificate.
Ultrasonic testing to EN 10228-3, SEP 1921 or ASTM A388 as agreed at order. Chemical analysis, mechanical test results and heat treatment records are reported on an EN 10204 3.1 certificate, or an EN 10204 3.2 certificate witnessed by a third party such as TUV, SGS, BV or Lloyd's Register. Dye penetrant testing, hardness testing, PMI and impact testing are available on request.
It is specified where alloy 625 corrosion resistance has to survive cyclic loading. Typical uses are metal bellows and expansion joints, flexible couplings and hoses, subsea and deepwater oil production hardware, chemical and plunger pump shafts, pressure vessel and heat exchanger tube sheets and flanges, valve bodies and seat rings, gas compressor and turbine parts, and mill equipment in cement, sugar, pulp and paper plants.
The alloy 625 base metallurgy is used from cryogenic temperatures up to about 980 to 1000 °C for oxidation resistance. Alloy 625LCF parts are usually limited by fatigue and by the design code rather than by oxidation, so bellows and cyclic service components are normally rated well below that ceiling. Confirm the allowable temperature against the design code that applies to your component.
Yes. Open-die forging needs no part specific dies, so single prototype pieces and small batches are practical. Send the drawing or dimensions, quantity, specification and required certification to sales@steelforgepieces.com for a quotation.
Jiangyin Jiangnan Metal Co., Ltd. is an open-die forging factory at No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China. For a quotation on Alloy 625LCF forgings, email sales@steelforgepieces.com or call +86-189-2135-9659 with the drawing or dimensions, grade, quantity, heat treatment condition and certification required.
We forge the full nickel alloy range. The grades most often compared with, or ordered alongside, Alloy 625LCF:
Page last updated 13 August 2026. The data above is given for guidance. Acceptance values for a specific order are those stated in the applicable specification and on the purchase order.