Nickel Alloy · Grade Datasheet and Forging Capability
MK20CDA Forgings: Rolled Rings, Flanges, Bars, Discs and Shafts
Nickel-cobalt-chromium precipitation-hardening superalloy, equivalent to Nimonic 105 and W.Nr. 2.4634, open-die forged to drawing from one piece.
MK20CDA is the AFNOR designation for a wrought nickel-cobalt-chromium superalloy, precipitation hardened by molybdenum, aluminium and titanium and rated for continuous service to about 950 °C. It is equivalent to Nimonic 105, Werkstoff 2.4634, NiCo20Cr15MoAlTi, UNS N13021 and BS HR3, and is delivered to DIN 17744. Jiangyin Jiangnan Metal Co., Ltd., an open-die forging factory in Jiangyin, Jiangsu, China, forges MK20CDA into seamless rolled rings, flanges, round bars, discs, shafts, sleeves, bushings, tube sheets and pipes from EAF + VOD + ESR melted stock, ultrasonically tested to EN 10228-3 and released with EN 10204 3.1 or 3.2 certification.
- Werkstoff
- 2.4634
- UNS
- N13021
- Max service temp.
- 950 °C
- Density
- 8.0 g/cm³
- Standard
- DIN 17744
- Melting
- EAF+VOD+ESR
MK20CDA equivalent grades and designations
The same alloy is bought under several different names. All designations below refer to one material and are interchangeable when raising an enquiry.
| Standard / system | Designation |
|---|---|
| AFNOR (France) | MK20CDA · NK20CDA · NCKD 20 ATv |
| Werkstoff number | 2.4634 |
| DIN designation | NiCo20Cr15MoAlTi |
| DIN standard | DIN 17744 |
| UNS (USA) | N13021 |
| BS (UK) | HR3 |
| ISO | NW 3021 |
| Aerospace material spec. | MSRR 7017 · MSRR 7018 |
| Common trade name | Nimonic 105 |
| Alloy family | Nickel-cobalt-chromium, gamma-prime precipitation hardening |
NIMONIC is a registered trademark of Special Metals Corporation. Cross-references are given for identification only. Jiangyin Jiangnan Metal Co., Ltd. is not affiliated with, sponsored by or endorsed by the trademark owner.
MK20CDA chemical composition
Composition to DIN 17744, in weight percent. Heat analysis is reported on every mill certificate we issue.
| Symbol | Element | Content, wt. % |
|---|---|---|
| Ni | Nickel | Balance |
| Co | Cobalt | 18.0 - 22.0 |
| Cr | Chromium | 14.0 - 15.7 |
| Mo | Molybdenum | 4.5 - 5.5 |
| Al | Aluminium | 4.5 - 4.9 |
| Ti | Titanium | 0.9 - 1.5 |
| C | Carbon | 0.17 max |
| Si | Silicon | 1.0 max |
| Mn | Manganese | 1.0 max |
| Fe | Iron | 1.0 max |
| Cu | Copper | 0.2 max |
| Zr | Zirconium | 0.15 max |
| B | Boron | 0.003 - 0.010 |
| S | Sulfur | 0.010 max |
| Pb | Lead | 0.0015 max |
Typical mechanical and physical properties
Room-temperature values for fully heat-treated forged bar. Properties vary with section size and heat-treatment cycle. The values released for your order are those on the EN 10204 certificate.
| Property | Typical value | Condition |
|---|---|---|
| Density | 8.0 g/cm³ | 20 °C |
| Melting range | 1290 - 1345 °C | — |
| Maximum service temperature | approx. 950 °C | Continuous, load bearing |
| Tensile strength, Rm | 1100 - 1250 MPa | 20 °C, solution + double aged |
| 0.2 % proof strength, Rp0.2 | 750 - 850 MPa | 20 °C, solution + double aged |
| Elongation, A5 | 16 - 25 % | 20 °C |
| Hardness | approx. 34 HRC (320 - 350 HB) | 20 °C |
| Crystal structure | FCC matrix with gamma-prime Ni3(Al,Ti) | — |
| Machinability rating | approx. 14 % | free-machining steel = 100 % |
Standard heat treatment
| Stage | Temperature | Time | Cooling |
|---|---|---|---|
| Solution treatment | 1150 °C | 4 h | Air cool |
| Intermediate treatment | 1050 °C | 16 h | Air cool |
| Precipitation ageing | 850 °C | 16 h | Air cool |
Alternative cycles are run to OEM or customer specification on request. MK20CDA is hot worked between 1100 and 1180 °C and machined with sharp, positive-rake carbide tooling at reduced speeds. Its machinability is roughly 14 % of free-machining steel, so allow generous machining stock on the forging.
MK20CDA forged product forms
Each shape below is open-die forged or ring-rolled to drawing. There is no fixed catalogue; the size is set by the part.
- Seamless rolled ringsRing-rolled, no weld seam, grain follows the circumference
- Forged flangesWN, SO, blind and special bores for vessels and valves
- Round bars and billetsForged, peeled or rough-turned; cut to length
- Discs and blanksUpset forged for turbine and gear blanks
- Shafts and spindlesStepped, hollow-bored or eccentric
- Sleeves and bushingsBored and stress-relieved before machining
- Tube sheetsSolid forged plate for shell and tube exchangers
- Forging rolls and pipesFurnace rolls, forged pipe and hollow sections
Size range
| Form | Outside diameter / width | Length / height / thickness |
|---|---|---|
| Seamless rolled rings | OD 200 - 3000 mm | Height max 1000 mm, wall 30 - 500 mm |
| Forged flanges | OD 100 - 2500 mm | Thickness 20 - 600 mm |
| Round bars | Dia. 60 - 900 mm | Length max 6000 mm |
| Discs and blanks | Dia. 100 - 2500 mm | Thickness 30 - 800 mm |
| Shafts and spindles | Dia. 80 - 800 mm | Length max 8000 mm |
| Sleeves and bushings | OD 100 - 2000 mm | Length max 3000 mm |
| Single-piece weight | 5 kg - 10 000 kg | Rough forged weight |
Sizes outside this range are quoted case by case. Send the finished-part drawing and we will propose the forging envelope, machining allowance and grain-flow direction.
Where MK20CDA forgings are used
Gamma-prime strengthening, the cobalt addition and creep resistance at 950 °C place MK20CDA in hot sections where cheaper nickel grades start to lose load capacity.
Gas turbines and power generation
- Turbine discs, ring sections and spacers
- Blade and vane forgings
- Gearbox, gas-compressor and power-transmission components
- Forged gears, spindles and bars
Oil, gas and offshore
- Subsea and deepwater production system parts
- Wellhead and Christmas tree components
- Valve bodies, stems, seat rings and blocks for ball, check, globe, gate and plug valves and strainers
- Industrial air compressors and nitrogen generators
Pressure vessels and heat exchangers
- Forged flanges, nozzles and tube sheets
- Shell and tube heat exchanger components
- Air receivers and pressure-vessel shells
- Columns, towers, tanks, silos and preheaters
Hot-work tooling and furnaces
- Hot working tools and high-temperature springs
- Die-casting inserts and cores
- Boiler tube supports and furnace components
- Heat-treatment fixtures and forging rolls
Engines and process equipment
- Automotive and marine exhaust valves
- Forged crankshafts and eccentric shafts
- Manifolds and forged wheels
- Crystallizer equipment and process modules
Nuclear and high-integrity work
- Forged nozzles and pieces for nuclear service
- Components requiring EN 10204 3.2 third-party release
- Parts with full traceability to heat number
Melting, forging and quality control
Melting route
MK20CDA is melted by electric arc furnace (EAF) with vacuum oxygen decarburisation (VOD), then electroslag remelted (ESR). ESR refines the solidification structure, reduces sulfur and non-metallic inclusions, and gives the through-section soundness that heavy superalloy forgings need. Vacuum induction melting with vacuum arc remelting (VIM+VAR) can be sourced for aerospace-critical parts on request.
Forging
Billets are heated into the 1100 to 1180 °C hot-working window and open-die forged or ring-rolled with controlled reduction ratio, so grain flow follows the loaded contour of the part instead of being cut through by machining. Forging is finished above the recrystallisation temperature to keep the structure fine and uniform.
Testing and certification
| Check | Standard |
|---|---|
| Ultrasonic testing | EN 10228-3 · SEP 1921 · ASTM A388 |
| Chemical analysis | Spectrometer, heat and product analysis |
| Mechanical testing | Tensile, hardness, impact as specified |
| Surface examination | Liquid penetrant (PT) on request |
| Dimensional report | Issued with every consignment |
| Certification | EN 10204 3.1 works certificate, or 3.2 countersigned by TUV / SGS / BV / Lloyd's |
| Traceability | Hard-stamped heat and piece number |
About the manufacturer
Jiangyin Jiangnan Metal Co., Ltd. operates an open-die forging plant in Jiangyin, Jiangsu Province, about two hours by road from Shanghai port. We forge carbon steel, alloy steel, tool steel, stainless steel and nickel-based superalloys into rings, flanges, bars, discs, shafts, sleeves and tube sheets, working from customer drawings rather than a stock catalogue. Export documentation, third-party inspection and container or break-bulk shipment are handled in house.
- Company
- Jiangyin Jiangnan Metal Co., Ltd., open-die forging factory
- Address
- No.1 Chengxiqiao Road, Zhouzhuang Town, Jiangyin City, Jiangsu Province, China
- Telephone
- +86 189 2135 9659 (WhatsApp / WeChat)
- sales@steelforgepieces.com
- Website
- www.steelforgepieces.com
- Nearest port
- Shanghai / Zhangjiagang, Jiangsu
- Minimum order
- 1 piece, prototypes and single spares accepted
- Lead time
- 25 to 45 days from drawing approval
MK20CDA frequently asked questions
What is MK20CDA?
MK20CDA is the AFNOR designation for a wrought nickel-cobalt-chromium superalloy strengthened by precipitation of the gamma-prime phase through molybdenum, aluminium and titanium additions. It is supplied to DIN 17744 and rated for continuous service to approximately 950 °C, combining the high strength of age-hardening nickel-base alloys with good creep resistance.
What is MK20CDA equivalent to?
MK20CDA is equivalent to Nimonic 105, Werkstoff number 2.4634, DIN designation NiCo20Cr15MoAlTi, UNS N13021, BS HR3, ISO NW 3021 and AFNOR NK20CDA / NCKD 20 ATv. It is also called out in the aerospace specifications MSRR 7017 and MSRR 7018.
What is the chemical composition of MK20CDA?
Nickel balance, cobalt 18.0 to 22.0 %, chromium 14.0 to 15.7 %, molybdenum 4.5 to 5.5 %, aluminium 4.5 to 4.9 %, titanium 0.9 to 1.5 %, carbon 0.17 % max, silicon 1.0 % max, manganese 1.0 % max, iron 1.0 % max, copper 0.2 % max, zirconium 0.15 % max, boron 0.003 to 0.010 %, sulfur 0.010 % max, lead 0.0015 % max. Full breakdown in the composition table.
What is the maximum service temperature of MK20CDA?
Approximately 950 °C (1740 °F) for continuous load-bearing service, with good creep and stress-rupture resistance in that range. Above 950 °C the gamma-prime strengthening phase coarsens and load capacity falls quickly, so higher-temperature applications usually move to a cobalt-base grade such as Haynes 188 or Haynes 25.
Which MK20CDA forged shapes can you supply?
Seamless rolled rings, forged flanges, round bars and billets, discs and blanks, shafts and spindles, sleeves and bushings, tube sheets, forged pipes and tubes, gear blanks, valve bodies, stems and seat rings, nozzles, crankshafts and forging rolls. Everything is forged to your drawing or size list. See product forms.
How is MK20CDA melted and certified?
EAF + VOD melting followed by ESR remelting. Forgings are ultrasonically tested to EN 10228-3, SEP 1921 or ASTM A388 as specified, and released with an EN 10204 3.1 works certificate or an EN 10204 3.2 certificate countersigned by a third-party inspection body such as TUV, SGS, BV or Lloyd's Register.
What heat treatment is applied to MK20CDA forgings?
The standard route is 1150 °C for 4 h, air cool, then 1050 °C for 16 h, air cool, then 850 °C for 16 h, air cool. Alternative cycles are run to OEM or customer specification.
What is the minimum order quantity and lead time?
One piece. We accept single prototype and repair-spare forgings. Typical lead time is 25 to 45 days from drawing approval, depending on size, heat-treatment cycle and testing scope. Email a drawing or a size list with the required standard to sales@steelforgepieces.com for a quotation.
Request an MK20CDA forging quotation
Send a drawing, a sketch, or the finished dimensions. We reply with price, forging envelope, machining allowance, heat-treatment route and delivery date, normally within one working day.
- Grade: MK20CDA / Nimonic 105 / 2.4634
- Form and finished dimensions
- Quantity and required delivery date
- Heat treatment and NDT requirements
- Certificate: EN 10204 3.1 or 3.2
- Delivery condition: rough forged or machined
Related nickel alloy forgings
Grades commonly cross-shopped against MK20CDA for hot-section forgings.
- Nimonic 80A2.4952, lower cost, service to about 815 °C
- WaspaloyN07001, turbine discs and fasteners
- Udimet 720Higher gamma-prime volume fraction, disc alloy
- Udimet 500Blade and disc forgings
- Inconel 706Large land-turbine disc forgings
- Rene 41High strength to 870 °C
- Haynes 188Cobalt base, above 950 °C
- Inconel 625Corrosion service, easier to weld
All nickel alloy grades we forge (A to Z)
- Alloy 59
- Alloy 602
- Hastelloy B
- Hastelloy B-2
- Hastelloy B-3
- Hastelloy B-4
- Hastelloy C-22
- Hastelloy C-276
- Hastelloy C-4
- Hastelloy C-2000
- Hastelloy G-3
- Hastelloy X
- Haynes 25
- Haynes 188
- Haynes 230
- Incoloy 800
- Incoloy 800H
- Incoloy 800HT
- Incoloy 825
- Incoloy 890
- Incoloy 901
- Incoloy 925
- Incoloy 926
- Incoloy 945
- Inconel 600
- Inconel 601
- Inconel 617
- Inconel 625
- Inconel 690
- Inconel 693
- Inconel 706
- Inconel 725
- Inconel X-750
- MK20CDA
- Monel 400
- Monel K-500
- Monel R-405
- MP159
- MP35N
- Multimet N155
- NI-SPAN-C Alloy 902
- Nimonic 75
- Nimonic 80A
- Rene 41
- Udimet 500
- Udimet 520
- Udimet 720
- UNS N07022
- UNS N07208
- UNS N07252
- Waspaloy
- Haynes 188 forged rings
- Waspaloy forged pipes
Technical data compiled and reviewed by the engineering team at Jiangyin Jiangnan Metal Co., Ltd. Values are typical and given for guidance. The figures that govern your order are those on the EN 10204 certificate issued with the goods. Last reviewed .