2.4668 (NiCr19Fe19Nb5Mo3) Forging Parts | China Manufacturer

Q: Is 2.4668 (NiCr19Fe19Nb5Mo3) the same as UNS N07718?

2.4668 (NiCr19Fe19Nb5Mo3) is the European EN/DIN/W.Nr. designation for UNS N07718 (ASTM) — the same precipitation-hardenable nickel-chromium superalloy. Both designations refer to identical chemical composition, mechanical properties, and performance. EN uses 2.4668, ASTM uses UNS N07718, and AMS uses AMS 5662/5663/5664.

Q: What is the maximum service temperature for 2.4668 alloy?

2.4668 (NiCr19Fe19Nb5Mo3) can be used continuously at temperatures up to 704°C (1300°F), with short-term service capability up to 815°C. For cryogenic applications, the alloy maintains excellent toughness and strength down to -217°C (-423°F), making it suitable for liquid hydrogen and liquid oxygen storage systems.

Q: Can you provide third-party inspection for 2.4668 forgings?

We support and facilitate third-party inspection for all 2.4668 forging parts, including inspection by BV, SGS, TÜV, and other internationally recognized inspection agencies. Client witness inspection at our factory during production, heat treatment, and testing is also available.

Q: What standards does 2.4668 (NiCr19Fe19Nb5Mo3) forging comply with?

Our 2.4668 forgings are manufactured in accordance with material requirements of: ASTM B637, AMS 5662/5663/5664, EN 10302, DIN 17752, API 6A (material and dimensional requirements), ASME Boiler and Pressure Vessel Code Sections II and VIII, and NACE MR0175/ISO 15156 sour service material requirements.

2.4668 (NiCr19Fe19Nb5Mo3) — Key Facts at a Glance

EN / DIN Designation: 2.4668 / NiCr19Fe19Nb5Mo3
UNS / ASTM Designation: N07718 (ASTM B637)
AMS Specification: AMS 5662 / AMS 5663 / AMS 5664
Max Service Temperature: 704°C (1300°F) continuous
Min Cryogenic Temp.: -217°C (-423°F)
UTS (min, heat treated): 1230 MPa
Max Bar Diameter: 2000 mm
Max Ring Diameter: 6000 mm
Mill Test Certificate: EN 10204 3.1 (standard) / 3.2 (on request)
Quality Certification: ISO 9001:2015
Lead Time (raw forging): 3–4 weeks
Global Delivery: 50+ countries worldwide

2.4668 (NiCr19Fe19Nb5Mo3) Forging Parts — Open Die Forgings, Seamless Rolled Rings, Bars & Shafts by Jiangsu Liangyi China — Custom 2.4668 (NiCr19Fe19Nb5Mo3) Forging Parts — Open Die Forgings, Seamless Rolled Rings, Bars & Shafts by Jiangsu Liangyi

Jiangsu Liangyi is a professional manufacturer in China certified to ISO 9001:2015, specializing in 2.4668 (NiCr19Fe19Nb5Mo3) open die forging parts and seamless rolled rings. With over 27 years of forging experience, we supply high-performance 2.4668 (NiCr19Fe19Nb5Mo3) nickel superalloy forgings to customers throughout Europe, North America, the Middle East, Southeast Asia, Australia, and more than 50 other countries worldwide. We provide full material traceability and meet international material standards including ASTM, EN, DIN, and ASME.

What is 2.4668 (NiCr19Fe19Nb5Mo3) Alloy?

2.4668 (also written as NiCr19Fe19Nb5Mo3) is a precipitation-hardenable nickel-chromium superalloy designated under the European EN/DIN standard system. This alloy is internationally recognized under several equivalent designations:

2.4668 (EN / DIN / W.Nr.) UNS N07718 (ASTM/UNS) AMS 5662 / 5663 / 5664 ASTM B637 API 6A material requirements

2.4668 NiCr19Fe19Nb5Mo3 has excellent high strength, corrosion resistance, and thermal stability over a wide temperature range — from -217°C for cryogenic use up to 704°C for continuous high-temperature service, and can withstand short-term use at 815°C.
Unlike regular stainless steels and common nickel alloys, 2.4668 NiCr19Fe19Nb5Mo3 can be easily made into intricate parts. It welds very well and highly resists cracking after welding. With excellent tensile, fatigue, creep, and stress-rupture strength, plus cost-effective production, 2.4668 forging parts are the best choice material for important industrial uses where failure cannot be tolerated.

Full Range of 2.4668 (NiCr19Fe19Nb5Mo3) Forged Products

We make custom 2.4668 (NiCr19Fe19Nb5Mo3) forging parts in a full range of shapes and sizes, and they are produced to meet your drawings and technical requirements. Our in-house production can handle single parts weighing from 30 kg up to 30 tons, and we offer complete CNC machining, heat treatment, and non-destructive testing (NDT) services.

Forged Bars & Rods

2.4668 forged round bars (max diameter up to 2000 mm)
NiCr19Fe19Nb5Mo3 square bars, flat bars & rectangular bars
NiCr19Fe19Nb5Mo3 step shafts, gear shafts & turbine rotor shafts

Seamless Rolled Rings

2.4668 seamless rolled forged rings (max diameter up to 6000 mm)
NiCr19Fe19Nb5Mo3 contoured rings, gear rings & seal rings
NiCr19Fe19Nb5Mo3 flanged rings & pressure vessel rings

Hollow Forgings & Sleeves

2.4668 seamless hollow bars & heavy-wall cylinders
NiCr19Fe19Nb5Mo3 sleeves, bushes, casings & housings
NiCr19Fe19Nb5Mo3 pipes, tubes & tubing shells for high-pressure service

Custom Forged Components

2.4668 forged discs, disks, blocks & plates
NiCr19Fe19Nb5Mo3 valve bodies, stems, balls & seat rings
2.4668 impellers, turbine disks, flanges & custom forgings

Jiangsu Liangyi Factory — 2.4668 (NiCr19Fe19Nb5Mo3) Forged Round Bars and Seamless Rolled Rings Production Line — Jiangsu Liangyi 27+ Years Forging Factory — 2.4668 (NiCr19Fe19Nb5Mo3) Production Line with Advanced Equipment

All our 2.4668 forging parts are fully produced with in-house CNC machining, surface treatment, and non-destructive testing (NDT), and they all meet your project requirements. Explore our full product range on our Products Page.

Chemical Composition of 2.4668 (NiCr19Fe19Nb5Mo3) Alloy

The chemical composition of our 2.4668 (NiCr19Fe19Nb5Mo3) forging parts strictly meets EN, ASTM, and AMS international standards, which guarantees consistent material performance, batch-to-batch stability, and full compliance with global industry requirements.

Table 1 — 2.4668 (NiCr19Fe19Nb5Mo3 / UNS N07718) Chemical Composition per EN 10302 / ASTM B637
Element	Min Content (%)	Max Content (%)	Core Function in Alloy
Nickel (Ni)	50	55	Provides base corrosion resistance and thermal stability
Chromium (Cr)	17	21	Improves oxidation and high-temperature corrosion resistance
Iron (Fe)	Balance		Improves alloy workability and reduces material cost
Niobium (Nb)	4.75	5.5	Enables precipitation hardening (γ″ phase) for increased strength
Molybdenum (Mo)	2.8	3.3	Boosts creep resistance and localized corrosion protection
Titanium (Ti)	0.65	1.15	Supports precipitation hardening (γ′ phase) and strength enhancement
Aluminum (Al)	0.2	0.8	Optimizes age-hardening response and grain matrix
Carbon (C)	—	0.08	Controls grain size and maintains weldability
Silicon (Si)	—	0.35	Deoxidizer during melting, improves castability
Manganese (Mn)	—	0.35	Improves hot workability and sulfide inclusion control
Phosphorus (P)	—	0.015	Strictly limited to maintain corrosion resistance
Sulfur (S)	—	0.015	Strictly limited to prevent hot cracking and embrittlement
Boron (B)	—	0.006	Improves hot workability and grain boundary strength
Cobalt (Co)	—	1.0	Incidental element; minor solid-solution strengthening

Standardized Heat Treatment for 2.4668 Forgings

We use precise, standardized heat treatment for all our 2.4668 (NiCr19Fe19Nb5Mo3) forged parts, adjusted to deliver better mechanical properties for your specific use. Our in-house heat treatment facility has 10 industrial furnaces with full temperature monitoring and documentation.

Process A — Heat Treatment for Optimal Tensile & Stress Rupture Properties

This process is recommended for high-temperature service parts (gas turbines, aerospace engine parts) where long-term creep and stress rupture resistance are important:

Solution annealing: Soak for 1 hour at 954°C to 982°C, followed by rapid air cooling
First age treatment: Hold for 8 hours at 718°C, then controlled cooling at 56°C/hour down to 621°C
Second age treatment: Hold for 8 hours at 621°C, followed by air cooling to room temperature

Process B — Heat Treatment for Cryogenic & Maximum Room-Temperature Strength

This process is optimized for cryogenic tankage, downhole drilling tools, and parts needing maximum room-temperature strength and toughness:

Solution annealing: Soak for 1 to 2 hours at 1066°C, followed by rapid air cooling
First age treatment: Hold for 8 hours at 718°C, then controlled cooling at 56°C/hour down to 621°C
Second age treatment: Hold for 8 hours at 621°C, followed by air cooling to room temperature

How to Choose: Process A vs. Process B — Engineer's Decision Guide

Choosing the right heat treatment for 2.4668 forgings depends on the main failure risk in your actual use. No single process works best for all cases — each is designed to balance material properties for specific needs. The table below shows Jiangsu Liangyi’s internal guide, built from over 27 years of application feedback from customers worldwide:

Heat Treatment Process Selection Guide for 2.4668 (NiCr19Fe19Nb5Mo3) Forging Parts
Selection Criterion	Choose Process A (954–982°C SA)	Choose Process B (1066°C SA)
Service Temperature	500°C–704°C (high-temp service)	Below 400°C or cryogenic (−217°C)
Primary Failure Concern	Creep, stress rupture, fatigue at temperature	Tensile overload, impact fracture, SCC
Grain Size Result	Fine-to-medium grain (ASTM 5–8)	Coarser grain (ASTM 3–5) — better creep path is not the goal here
Typical Room-Temp UTS	1280–1380 MPa	1330–1420 MPa (slightly higher)
Stress Rupture Life (704°C)	Superior — optimized for this regime	Inferior — coarser SA temp dissolves δ phase boundary pins
Charpy Impact (−196°C)	Good, ≥ 40 J typical	Excellent, ≥ 55 J typical
Recommended Applications	Turbine discs, compressor blades, combustion casings, steam valve internals	Downhole drill collars, cryogenic vessel rings, wellhead bodies, subsea bolting
AMS Specification Alignment	AMS 5663 (bar) / AMS 5664 (ring)	AMS 5662 (bar) — standard aerospace bar condition

Note: Both processes use the same double-aging settings. Only the solution annealing temperature differs, but this creates very different δ-phase (Ni₃Nb) distributions that determine long-term performance. If you are unsure, send us your operating conditions and our technical team will recommend the best heat treatment for you at no cost.

Mechanical Properties of 2.4668 Forged Round Bars

After standardized heat treatment, our 2.4668 (NiCr19Fe19Nb5Mo3) forged round bars meet and exceed international industry standards, with guaranteed mechanical properties for every batch.

Table 2 — 2.4668 (NiCr19Fe19Nb5Mo3) Forged Round Bar Mechanical Properties (Heat Treated Condition)
Mechanical Property	Guaranteed Min Value	Typical Tested Value	Test Condition
Ultimate Tensile Strength (Rm)	1230 MPa	1300–1400 MPa	Fully Heat Treated (+AT)
0.2% Offset Yield Strength (Rp0.2)	1030 MPa	1100–1200 MPa	Fully Heat Treated (+AT)
Elongation at Fracture (A)	12%	15–20%	Fully Heat Treated (+AT)
Hardness	—	38–44 HRC	Fully Heat Treated (+AT)

High-Temperature Mechanical Properties of 2.4668 Forgings

Room-temperature properties alone are not enough when designing parts for high-temperature use. The table below shows how the strength of our fully heat-treated 2.4668 (NiCr19Fe19Nb5Mo3) forged bars drops at different temperatures (Process A condition), based on our internal test data. Engineers designing turbines, valves, and pressure-retaining parts should use these values for high-temperature design limits.

Table 2B — 2.4668 (NiCr19Fe19Nb5Mo3) Forged Bar: Elevated-Temperature Tensile Properties (Process A, Fully Aged)
Test Temperature	UTS Rm (MPa)	0.2% Yield Rp0.2 (MPa)	Elongation A (%)	Reduction of Area Z (%)	Practical Significance
Room Temp. (21°C)	1310–1400	1100–1200	16–20	18–22	Baseline — design reference
204°C (400°F)	1260–1345	1075–1160	16–19	17–21	~4% strength reduction — negligible for most designs
427°C (800°F)	1210–1295	1050–1130	16–19	17–21	~8% reduction — begin applying temperature factors in design
538°C (1000°F)	1145–1220	1010–1090	17–20	18–22	Strength still excellent — suitable for turbine compressor stages
649°C (1200°F)	1010–1090	930–1010	18–21	19–23	~22% reduction — approaching upper boundary for sustained service
704°C (1300°F)	920–1000	840–910	18–22	19–24	Maximum recommended continuous service — consult creep data for life calculation

Note: Values above represent typical tested data from our production forgings. Actual values vary with bar diameter, reduction ratio, and section thickness. Contact our technical team for location-specific test data on large cross-sections (> Ø 250 mm).

Physical & Thermal Properties of 2.4668 (NiCr19Fe19Nb5Mo3)

The physical and thermal properties below are essential for design engineers carrying out FEA (finite element analysis), stress analysis, thermal management calculations, and CTE mismatch checks in multi-material parts. Unlike room-temperature mechanical strength, which can be adjusted by heat treatment, the physical properties of 2.4668 come from the alloy’s chemical makeup and stay almost the same no matter which heat treatment is used.

Table 2C — 2.4668 (NiCr19Fe19Nb5Mo3 / UNS N07718) Physical & Thermal Properties
Property	Value	Temperature Condition	Design Engineering Note
Density	8.19 g/cm³	Room temperature	~3% denser than 316L SS — factor into rotating part mass balance calculations
Melting Range	1260–1336°C	—	Solidus at 1260°C; hot forging must stay below this to avoid incipient melting at grain boundaries
Elastic Modulus (E)	200 GPa	21°C	Drops to ~172 GPa at 538°C — critical for deflection and resonance calculations at temperature
Shear Modulus (G)	77.2 GPa	21°C	Use for torsional stiffness calculations in shaft and coupling designs
Poisson's Ratio (ν)	0.294	21°C	Stable across temperature range — standard value used in most FEA models
Thermal Conductivity	11.4 W/m·K	21°C	Low conductivity (~16× lower than copper) — thermal gradient buildup in thick sections; slow furnace heating recommended
Thermal Conductivity	17.8 W/m·K	538°C	Conductivity improves with temperature — favorable for heat exchanger service
Thermal Conductivity	20.8 W/m·K	760°C	—
CTE (Mean Linear)	13.0 μm/m·°C	21–93°C range	Lower CTE than austenitic SS (17.2) — verify joint expansion compatibility in dissimilar-metal assemblies
CTE (Mean Linear)	13.3 μm/m·°C	21–316°C range	—
CTE (Mean Linear)	14.4 μm/m·°C	21–649°C range	Rising CTE at temperature — account for differential thermal growth in bolted flange joints
Specific Heat Capacity	435 J/kg·K	21°C	Higher than carbon steel (490 J/kg·K) — slower thermal cycling recommended to prevent surface-to-core ΔT cracking
Electrical Resistivity	1.25 μΩ·m	21°C	High resistivity — not suitable for electrical conductor applications; no concern for most structural uses
Magnetic Permeability	≤ 1.0011 μ	Room temperature	Essentially non-magnetic — compatible with MRI, electromagnetic sensing, and magnetically sensitive equipment environments

2.4668 (NiCr19Fe19Nb5Mo3) vs. Other Common Nickel Alloys — Quick Comparison

The table below provides a direct comparison of 2.4668 against the most commonly considered nickel superalloys to help engineers select the right material for their application:

Table 3 — 2.4668 (NiCr19Fe19Nb5Mo3) vs. NiCr22Mo9Nb (2.4856), NiMo16Cr15W (2.4819 / Hastelloy® C276), and Waspaloy® (UNS N07001)
Property	2.4668 (NiCr19Fe19Nb5Mo3)	2.4856 / Inconel 625	2.4819 / Hastelloy® C276	Waspaloy® (UNS N07001)
UTS (heat treated)	1230–1400 MPa	827–1034 MPa	690–793 MPa	1275–1480 MPa
Max Service Temp. (continuous)	704°C (1300°F)	816°C (1500°F)	649°C (1200°F)	870°C (1598°F)
Strengthening Mechanism	Precipitation hardening (γ″)	Solid-solution	Solid-solution	Precipitation hardening (γ′)
Corrosion Resistance	Excellent	Superior	Outstanding (acids)	Good
Weldability	Excellent	Excellent	Good	Moderate (SHT required)
Primary Applications	Turbine discs, shafts, wellheads	Marine, chemical, offshore	Chemical processing, FGD	Jet engine hot sections
Relative Cost	$$ (moderate)	$$$ (higher Nb content)	$$$ (high Mo & W content)	$$$$ (Co-bearing)

Hastelloy® is a registered trademark of Haynes International, Inc. Waspaloy® is a registered trademark of RTX Corporation. Both names are used in this comparison table for informational and descriptive purposes only. Jiangsu Liangyi does not manufacture or sell Hastelloy® or Waspaloy® branded products.

2.4668 Open Die Forging Process — From Ingot to Finished Component

For engineers who choose important parts, it is important to understand how 2.4668 (NiCr19Fe19Nb5Mo3) is forged, and why forged parts perform far better than cast ones. With 27 years of experience making nickel superalloy forgings, Jiangsu Liangyi has developed a precise, multi-step process specially optimized for the hot working properties of this alloy.

Hot Working Temperature Window for 2.4668

2.4668 (NiCr19Fe19Nb5Mo3) has a comparatively narrow hot working window relative to austenitic stainless steels, needing precise temperature control at every stage of the forging sequence. Our process engineers keep the following temperature disciplines on every production run:

2.4668 (NiCr19Fe19Nb5Mo3) Hot Forging Process Parameters — Jiangsu Liangyi Production Standard
Process Stage	Temperature Range	Critical Control Requirement	Consequence of Deviation
Ingot Soaking (pre-forge)	1120–1177°C	Uniform soak for minimum 1 hr per 25 mm cross-section	Cold spots cause hot tearing at corners and billet center
Initial Breakdown Forging	1095–1165°C	Forging above δ-phase solvus (~1010°C) to homogenize cast structure	Undissolved Laves phase clusters → internal segregation bands
Intermediate Reheats	1040–1120°C	No deformation below 954°C — risk of surface cracking rises sharply	Adiabatic shear bands and surface lap defects in die radii
Final Shape Forging	982–1066°C	Controlled strain rate; reduction per pass ≤ 30% to avoid dynamic strain aging	Localized grain coarsening ("necklace" microstructure) at shear zones
Seamless Ring Rolling	982–1050°C	Ring growth rate ≤ 3 mm/sec to maintain uniform deformation through wall thickness	Through-thickness grain size gradient; OD-to-ID property variation
Slow Cooling (post-forge)	Furnace-cool to ≤ 315°C	Avoid quenching; stress equalization before heat treatment	Quench cracking in thick-wall sections (>100 mm wall thickness)

Total Reduction Ratio & Forging Quality Grades

The forging reduction ratio — the ratio between the cross-section area of the original ingot and that of the finished forged part — directly shows internal quality. Higher reduction ratios make the internal matrix denser, refine grain size, and improve mechanical properties. Jiangsu Liangyi sets minimum reduction ratios for each material grade:

Standard Industrial Grade

Minimum total reduction ratio: ≥ 4:1
Application: General industrial valves, flanges and pressure vessels
Certification: EN 10204 3.1 Mill Test Certificate (standard)
Ultrasonic testing: ASTM E388 Class B

Premium Aerospace / Nuclear Grade

Minimum total reduction ratio: ≥ 6:1
Application: Turbine discs, rotating shaft, nuclear reactor parts
Certification: EN 10204 3.2 + third-party witness
Ultrasonic testing: ASTM E388 Class B standard; AMS 2631 or stricter class per customer specification

Why Choose Forgings Over Castings for 2.4668 Components?

When buying 2.4668 (NiCr19Fe19Nb5Mo3) parts, engineers often ask whether investment castings or forgings are better. The answer depends on shape, load conditions, and how important the part is — but for most structural, pressure-holding, and rotating uses, open die forgings provide clearly better reliability. Here is a direct technical comparison:

2.4668 Open Die Forgings vs. Investment Castings — Technical Comparison for Critical Applications
Criterion	Open Die Forgings (Jiangsu Liangyi)	Investment Castings (typical)
Internal Porosity	Zero porosity — full densification under multi-directional compressive force	Shrinkage porosity common in thick sections; requires HIP (Hot Isostatic Pressing) for critical use
Grain Structure	Refined, wrought, worked grain — uniform through full cross-section	Coarse, columnar, directional dendrite structure from solidification
Tensile Strength (typical)	UTS 1300–1400 MPa (heat treated)	UTS 1100–1250 MPa (even after HIP)
Fatigue Life	significantly longer high-cycle fatigue life vs. equivalent casting (typically 2–5× per published comparative data)	Fatigue notch sensitivity from dendritic micro-segregation and pore initiation sites
Charpy Impact Energy	≥ 40 J at room temperature	15–30 J typical — not recommended for impact or shock load service
NDT Detectability	Clean UT signal — easy volumetric inspection to tight acceptance criteria	Cast noise scatter — UT interpretation difficult; higher reject rate after NDE
Maximum Section Size	Up to 2000 mm Ø bar, 6000 mm Ø ring, 30-ton single piece	Limited to ~500 mm max dimension for quality castings
Geometry Complexity	Best for axisymmetric, near-net round shapes — bars, rings, shafts, discs, blanks	Better for complex, thin-wall, non-axisymmetric shapes with internal passages
Applicable Standards	ASTM B637, AMS 5662/5663/5664, API 6A, ASME Sec. VIII	AMS 5383 (casting) — lower allowable stress values in ASME codes
Recommended Use Case	All rotating, pressure-retaining, and fatigue-critical applications	Static, low-stress, intricate-geometry parts where forging tooling cost is prohibitive

Weldability of 2.4668 (NiCr19Fe19Nb5Mo3) Forgings — What Fabricators Need to Know

One main advantage of 2.4668 (NiCr19Fe19Nb5Mo3) over other high-strength nickel superalloys is its excellent resistance to post-weld strain-age cracking. Alloys such as Waspaloy or René 41 are very hard to weld without intricate pre-weld and post-weld steps, but 2.4668 avoids this issue. This better weldability comes from its special strengthening method: the γ″ (Ni₃Nb) precipitates that give 2.4668 its high strength form slowly during aging. This allows production teams enough time to complete post-weld steps before hardening locks in residual stresses.

Recommended Welding Consumables for 2.4668 Forgings

Welding Consumables for 2.4668 (NiCr19Fe19Nb5Mo3) Forgings — by Process
Welding Process	Recommended Filler / Electrode	AWS Classification	Notes
GTAW (TIG)	Inconel Filler Metal 718	AWS A5.14 ERNiFeCr-2	Preferred process for root passes, thin sections, and precision welds. Produces lowest heat input and best joint integrity.
GMAW (MIG)	Inconel Filler Metal 718	AWS A5.14 ERNiFeCr-2	Acceptable for fill and cap passes on heavier sections. Spray transfer mode preferred to minimize spatter and heat-affected zone width.
SMAW (Stick)	Inconel Electrode 718	AWS A5.11 ENiCrFe-7	Acceptable for field repair and less-important welds. Keep short arc length and inter-pass temperature ≤ 150°C.
SAW (Submerged Arc)	ERNiFeCr-2 wire + matching flux	AWS A5.14	For large section joining only. High heat input requires careful inter-pass temperature control and post-weld cooling rate management.
EBW / LBW	Autogenous (no filler)	—	Preferred for aerospace-grade joints needing minimum heat affected zone. Needs post-weld aging treatment to restore full strength.

Pre-Weld & Post-Weld Heat Treatment Requirements

Pre-weld condition: Weld 2.4668 forgings in the solution-annealed (SA) condition, before aging, wherever possible. Welding fully aged material introduces high residual stresses that increase cracking risk during any subsequent thermal cycle.
Pre-heat temperature: Not strictly needed for thin sections (< 12 mm). For sections ≥ 12 mm, preheat to 25–93°C minimum to remove moisture and reduce thermal shock. Avoid preheating above 150°C — elevated preheat on nickel alloys can increase sensitization risk.
Inter-pass temperature: Keep ≤ 150°C (measured with contact thermocouple, not pyrometer) between passes. Higher inter-pass temperatures accelerate δ-phase precipitation in the HAZ, which reduces ductility margins.
Post-weld heat treatment (PWHT): Full solution anneal + double-age (Process A or B, per application) restores 100% of base-metal mechanical properties. If full PWHT is not feasible, a stress-relief at 620–650°C for 4–8 hours recovers > 90% of properties with significantly lower distortion risk.
Shielding gas: 100% argon (GTAW) or 75% Ar / 25% He (GMAW) for best arc stability and weld pool protection. No CO₂ shielding — carbon contamination degrades corrosion resistance in HAZ.

Corrosion Resistance of 2.4668 (NiCr19Fe19Nb5Mo3) in Industrial Service Environments

Corrosion resistance is one of the most important features of 2.4668 (NiCr19Fe19Nb5Mo3) for use in oil and gas, nuclear power, and chemical processing. Unlike many high-strength alloys that give up corrosion resistance for strength, 2.4668’s chemical makeup offers excellent protection in many different environments. Its 17–21% chromium forms a stable protective oxide layer, while 2.8–3.3% molybdenum helps resist pitting corrosion. The chart below, based on Jiangsu Liangyi’s project experience and published corrosion data, gives practical advice for choosing the right material for specific working environments:

2.4668 (NiCr19Fe19Nb5Mo3) Corrosion Resistance Matrix — By Service Environment
Service Environment	Resistance Rating	Key Mechanism	Typical Corrosion Rate	Engineering Notes
H₂S (Sour Service) — NACE MR0175	✅ Excellent	Ni matrix resists sulfide stress cracking (SSC); Cr passivates surface	< 0.025 mm/year (sweet field conditions)	When fully heat-treated to a hardness of ≤ 40 HRC, the 2.4668 (NiCr19Fe19Nb5Mo3) alloy meets the material requirements of NACE MR0175 / ISO 15156-3 for sour service applications up to 260°C.To comply with SSC standards, the material must be in fully heat-treated condition with hardness ≤ 40 HRC.
CO₂ / Sweet Corrosion (Downhole)	✅ Excellent	Cr-rich passive film prevents FeCO₃ scaling	Essentially nil at pH > 5	Superior to 13Cr and duplex SS in high-CO₂, high-temperature downhole environments.
Chloride Solutions (Seawater)	✅ Good	Mo content raises pitting resistance equivalent (PREN ≈ 24)	< 0.05 mm/year in aerated seawater at 25°C	Not subject to pitting or crevice corrosion in typical seawater at ambient temperature. At elevated temperature (> 80°C), consider 2.4856 (Inconel 625) for superior chloride performance.
High-Temperature Oxidation (Air)	✅ Excellent to 704°C	Cr₂O₃ scale provides adherent, low-growth-rate protection	Scale growth < 0.02 mg/cm²·hr at 700°C	Continuous service to 704°C without protective coating required. Above 760°C, scale spallation risk increases — consult our team for coating options.
Sulfuric Acid (H₂SO₄)	⚠️ Moderate — concentration-dependent	Passive film stability depends on acid concentration and temperature	1–5 mm/year in 10–50% H₂SO₄ at 25°C	Acceptable in dilute < 10% H₂SO₄ at room temperature. Above 50°C or in concentrated acid, consider 2.4819 (Hastelloy C276).
Hydrofluoric Acid (HF)	⚠️ Limited	Ni resists HF better than Fe-based alloys	Moderate — exact rate highly concentration/temp dependent	Not recommended for continuous HF service. Consult with Liangyi technical team on alloy substitution for HF-dominant environments.
Phosphoric Acid (H₃PO₄)	✅ Good	Ni-Cr passive film stable in phosphoric media	< 0.25 mm/year in pure H₃PO₄ at 25°C	Widely used in fertilizer plant piping, valve bodies, and pump casings where H₃PO₄ is present.
Caustic (NaOH / KOH)	✅ Excellent	High Ni content inherently resists caustic stress corrosion	Essentially nil below 80°C	Unlike stainless steels, 2.4668 does not suffer caustic stress corrosion cracking (CSCC) at concentrations up to 50% NaOH.
Cryogenic Service (LH₂ / LO₂ / LN₂)	✅ Excellent to −217°C	FCC crystal structure retains ductility; no ductile-brittle transition	Zero corrosion in clean cryogenic fluids	No special material condition needed for cryogenic service. Verify impact properties (Charpy at −196°C) are documented in MTR for safety-critical cryogenic applications.

Rating key: ✅ Excellent / Good = suitable for standard service without inhibitors; ⚠️ Moderate / Limited = acceptable under controlled conditions or concentration limits; ❌ Not recommended = consider alternative alloy. Contact Jiangsu Liangyi's technical team for project-specific corrosion assessment at no charge.

Dimensional Tolerances & Delivery Conditions for 2.4668 Forging Parts

Jiangsu Liangyi supplies 2.4668 (NiCr19Fe19Nb5Mo3) forged parts in four standard delivery conditions, ranging from raw forged blanks to precision-machined, fully tested parts ready for assembly. The delivery condition sets the dimensional tolerance, surface finish, and inspection scope for each order. Choose the condition that best fits your internal machining ability and project schedule:

Jiangsu Liangyi 4-Tier Delivery Condition System — 2.4668 (NiCr19Fe19Nb5Mo3) Forging Parts
Delivery Condition	Dimensional Tolerance	Surface Finish (Ra)	Included Inspection	Typical Lead Time	Best For
Condition 1 — As-Forged + Heat Treated	+10 / −0 mm on forging dimensions; per AMS 2374 or EN 10243-1	Ra 12.5–50 μm (as-forged scale)	Chemical analysis, mechanical test (tensile + hardness), UT (ASTM E388 Class B), dimensional check, EN 10204 3.1 MTC	3–4 weeks	Customers with in-house CNC machining capability; maximum material for custom profiling
Condition 2 — Rough Machined (RM)	+3 / −0 mm on finished drawing dimensions; OD / ID / face turned	Ra 3.2–6.3 μm (turned surfaces)	All Condition 1 inspection + dimensional report to turned surfaces	4–5 weeks	Customers who need near-net geometry but will perform finish machining to final tolerance in-house
Condition 3 — Semi-Finish Machined (SFM)	+0.5 / −0 mm on finished drawing dimensions; IT10–IT11 tolerance grade	Ra 1.6–3.2 μm	All Condition 2 + CMM dimensional report; PT/MT surface inspection	5–6 weeks	Customers needing minimal final machining; reduces total machining cost significantly
Condition 4 — Finish Machined to Drawing (FM)	Per customer drawing; typically IT7–IT8; ±0.05 mm on critical bores	Ra 0.8–1.6 μm standard; Ra 0.4 μm (mirror) on sealing faces available on request	All Condition 3 + full CMM report to drawing; EN 10204 3.1 MTC standard; EN 10204 3.2 available upon request with client-arranged third-party inspector; 100% dimensional acceptance	6–8 weeks	Direct-to-assembly components; eliminates in-house machining entirely; suitable for emergency replacement parts

We also offer these optional extra services for all forged parts: anti-rust oil coating, export-grade wooden crate packing, third-party inspection witness, positive material identification (PMI testing), and fast air freight for urgent orders. Please let our sales team know your exact delivery requirements when asking for a quote.

Quality Control & Inspection Standards

At Jiangsu Liangyi, we implement a full range of quality control systems for all 2.4668 (NiCr19Fe19Nb5Mo3) forging parts, from raw material melting to final delivery. Our quality management system is ISO 9001:2015 certified, and it meets API 6A, ASME, and EN material standards.

High-Purity Melting Processes

All our 2.4668 (NiCr19Fe19Nb5Mo3) forgings are made of premium raw materials, using advanced melting processes to guarantee material purity and homogeneity:

Double Melting (VIM + VAR): Vacuum Induction Melting + Vacuum Arc Remelting, standard for most industrial applications
Triple Melting (VIM + ESR + VAR): Premium grade for aerospace, nuclear, and ultra-critical applications

All our 2.4668 forging material is thoroughly forged to guarantee full internal densification, with a homogeneous microstructure free from blisters, cracks, and harmful slag inclusions. View our full production capabilities on our Equipment Page.

Inspection Standards & Certification

Every batch of 2.4668 forging parts is given rigorous inspection and testing in our in-house laboratory, with full documentation for complete traceability:

ASTM A604: Macroetch testing for remelted steel bars and billets
ASTM E112: Average grain size determination
EN ISO 6892-1:2020: Ambient temperature tensile testing
ISO 204:2009: Uniaxial tensile creep testing
EN 10204: Metallic products inspection documentation standards
ASTM E1409 / E1810: Oxygen and nitrogen analysis by inert gas fusion
NACE MR0175 / ISO 15156: Sour service material qualification

All finished products come with EN 10204 3.1 Mill Test Certificates as standard. EN 10204 3.2 (third-party countersigned) is available upon request, along with heat treatment records and NDT reports. We keep all production documents for at least 15 years after delivery.

Industry Applications & Verified Global Project Cases

Our 2.4668 (NiCr19Fe19Nb5Mo3) forged parts are widely used in main industrial applications that need outstanding performance under extreme temperatures, high pressure, and corrosive conditions. Below we list the specific forged parts we make for each industry, the applicable standards, and verified project references from our global delivery record.

Aerospace Industry

2.4668 (NiCr19Fe19Nb5Mo3) is the most widely used nickel superalloy in aerospace, making up an estimated 35–45% of all superalloy material used in modern commercial jet engines. It has high tensile strength, excellent fatigue life, and is easy to be produced, so that it is the standard choice for important rotating engine parts where failure is not an option.

Verified Project Case:We supplied custom 2.4668 forged turbine engine parts to a leading European aerospace tier-1 manufacturer, and all parts were produced to meet AMS 5663 (for disk forgings) and AMS 5664 (for ring forgings) material specifications. EN 10204 3.1 MTC is provided as standard; EN 10204 3.2 is available upon request with third-party inspection arranged.

Forged Component	Forging Form	Key Requirement	Applicable Standard
Turbine discs / compressor discs	Closed die disc forging	High LCF life; tight grain size ASTM 5–8	AMS 5663 / AMS 5664
Turbine spacer rings	Seamless rolled ring	Uniform properties OD-to-ID; tight OOR tolerance	AMS 5664 / EN 10302
Engine casing rings & flanges	Seamless rolled ring	Minimum weight; tight dimensional tolerance; low porosity	AMS 5664
High-temperature bolts & fasteners	Forged bar / billets	Consistent hardness 36–44 HRC; full surface coverage MT	AMS 5662 / ASTM F2281
Rotor shafts & stub shafts	Open die bar / step shaft	Excellent fatigue life; full UT per customer specification (AMS 2631 or equivalent)	AMS 5662 / ASTM B637
Combustion casing segments	Forged ring / arc segment	Oxidation resistance at 600–704°C	AMS 5664

Oil & Gas Industry (Onshore, Offshore & Subsea)

NiCr19Fe19Nb5Mo3 forged parts provide excellent resistance to sulfide stress cracking (SSC), hydrogen-induced cracking (HIC), and corrosion in harsh downhole, wellhead, and subsea environments. It meets NACE MR0175 standards and API 6A material requirements. Because of its high tensile strength, 2.4668 becomes the best choice material for sour service wellhead and completion equipment worldwide.
Verified Project Case:We supplied 2.4668 forged wellhead and Christmas tree parts for a large Middle East oilfield project, and they were used for 5,000 psi working pressure and sour service under NACE MR0175 Zone 3.(Note: Official API 6A Monogram licensing needs to be confirmed — please contact our sales team.)

Forged Component	Forging Form	Key Requirement	Applicable Standard
Wellhead casing hangers & tubing hangers	Custom forged disc / ring	Meets NACE MR0175 material requirements; ≤ 40 HRC hardness in heat-treated condition	API 6A material req. / NACE MR0175
Blowout preventer (BOP) bodies	Open die block forging	15,000–20,000 psi design; full volumetric UT; manufactured to API 6A material requirements	API 6A material req. / API 16A
Gate valve bodies, bonnets & flanges	Open die block / ring	Manufactured to API 6A material requirements; full PMI; EN 10204 3.1 MTC (3.2 on request)	API 6A material req. / ASME B16.34
Ball valve balls & seats	Forged bar / disc	Tight roundness tolerance; Ra 0.4 μm sealing face	API 6A material req. / NACE MR0175
Drill collar & downhole tool components	Forged bar / step shaft	High impact energy; manufactured to AMS 5662 material requirements; MPI inspection	AMS 5662 / API 5DP
Subsea connector hubs & clamps	Forged ring / flange	Seawater corrosion resistance; VIV fatigue life	API 6A material req. / DNV GL
Christmas tree mandrel & cross-overs	Open die bar forging	High-pressure bore; UT per customer specification; meets NACE MR0175 material requirements	API 6A material req. / ISO 10423

Power Generation & Nuclear Engineering

2.4668 forgings are the industry standard for industrial gas turbines, steam turbines, and nuclear power systems. This alloy has excellent creep resistance up to 704°C, and when made using triple melting (VIM + ESR + VAR), it achieves nuclear-grade purity, making it very important for power generation equipment that needs to operate reliably for decades.

Verified Project Case: We produced 2.4668 forged steam turbine valve internals and nuclear reactor coolant pump shaft parts for power plant operators in Asia, with full third-party inspection and EN 10204 3.2 certification.

Forged Component	Forging Form	Key Requirement	Applicable Standard
Gas turbine compressor discs	Disc forging	Creep life typically exceeding 100,000 hrs at 600°C per published alloy reference data; grain ASTM 5–8	AMS 5663 / EN 10302
Steam turbine valve spindles & stems	Forged bar / shaft	High-temperature strength; corrosion resistance in steam	EN 10302 / ASME Sec. VIII
Nuclear reactor coolant pump shafts	Open die step shaft	VIM+ESR+VAR triple-melt; low delta ferrite; full NDT	EN 10302 / ASME Sec. II material requirements
Steam turbine retaining rings	Seamless rolled ring	High tensile + fatigue; tight OOR; full UT	ASTM A289 / EN 10302
Nuclear valve bodies & bonnets	Block / ring forging	Triple-melt VIM+ESR+VAR; positive material identification (PMI); full volumetric UT	EN 10302 / ASME Sec. II material requirements
Generator rotor retaining rings	Large seamless ring	Non-magnetic (μ ≤ 1.005); high yield strength	ASTM A289 / IEC 60034

Petrochemical & General Industrial Applications

2.4668 (NiCr19Fe19Nb5Mo3) forgings are widely used in many high-value industrial applications where high temperatures, high pressures, or corrosive fluids make cheaper materials unsuitable.

Verified Project Case:We supplied custom 2.4668 forged extrusion press tooling (dies and mandrels) and heat exchanger tube sheets for chemical processing plants in Europe and North America, with full dimension test and EN 10204 3.1 certification; EN 10204 3.2 is available upon request.

Forged Component	Forging Form	Key Requirement	Application Context
Extrusion press dies & mandrels	Forged die block / bar	High hardness (≥ 38 HRC); wear resistance; thermal fatigue life	Metal extrusion of aluminium, copper, titanium billets at 300–500°C
Heat exchanger tube sheets	Forged disc / plate	High-integrity bored holes; corrosion resistance in process media	Urea synthesis, phosphoric acid, petrochemical reactors
Autoclave & pressure vessel closures	Forged ring / flange	ASME rated; full UT; EN 10204 3.2	High-pressure chemical reactors operating at > 200°C and > 100 bar
Pump impellers & wear rings	Custom near-net forging	Corrosion fatigue resistance; dimensional accuracy	Pumps handling H₂SO₄, phosphoric acid, saline solutions
Injection mold tooling inserts	Forged bar stock	Hardness 38–42 HRC post-aging; mirror-finish capable	High-cavity injection molds for engineering polymers requiring > 1 million cycles
High-pressure valve stems & spindles	Forged bar / machined shaft	NACE compliance; Ra 0.8 μm stem surface	High-pressure, high-temperature shut-off and control valves in refinery service

Frequently Asked Questions (FAQ)

Is 2.4668 (NiCr19Fe19Nb5Mo3) the same as UNS N07718?

2.4668 (NiCr19Fe19Nb5Mo3) is the European EN/DIN/Werkstoff designation for UNS N07718 (ASTM) — the same precipitation-hardening nickel‑chromium superalloy.
Both designations describe identical chemical composition, mechanical properties, and performance behavior, and are fully interchangeable in all industrial applications. EN standards use 2.4668, ASTM uses UNS N07718, and AMS specifications are listed as AMS 5662/5663/5664.

What is the maximum service temperature for 2.4668 alloy?

2.4668 (NiCr19Fe19Nb5Mo3) can operate continuously at temperatures up to 704°C (1300°F) and withstand short‑term use up to 815°C. For cryogenic service, it keeps excellent toughness and strength down to -217°C (-423°F), making it ideal for liquid hydrogen and liquid oxygen storage systems.

What is the lead time for custom 2.4668 forging parts?

Standard lead time for custom 2.4668 (NiCr19Fe19Nb5Mo3) forging parts is 3–4 weeks for raw forgings, and 4–6 weeks for fully machined, heat treated, and tested parts. We can accommodate expedited production for urgent project requirements, with lead times as short as 2 weeks for important orders.

Can you provide third-party inspection for 2.4668 forgings?

We fully support and arrange third-party inspection for all our 2.4668 (NiCr19Fe19Nb5Mo3) forged parts. Customers may appoint internationally recognized inspection bodies such as BV, SGS, TÜV, or any other preferred agency. We also welcome on-site witness inspections at our factory during production, heat treatment, and testing at any stage.

What international standards do your 2.4668 forgings comply with?

Our 2.4668 forging parts meet a comprehensive set of international standards, including: ASTM B637 (nickel alloy bars and forgings), AMS 5662 / 5663 / 5664 (aerospace material specification), EN 10302 (heat-resisting steels and nickel alloys), DIN 17752, API 6A (material and dimensional requirements for wellhead and Christmas tree equipment), ASME Boiler and Pressure Vessel Code Sections II and VIII (material requirements), and NACE MR0175 / ISO 15156 sour service material requirements.

What is the difference between 2.4668 (NiCr19Fe19Nb5Mo3) and 2.4856 (NiCr22Mo9Nb)?

2.4668 (NiCr19Fe19Nb5Mo3) is a precipitation-hardened alloy with high tensile strength, and its ultimate tensile strength (UTS) can reach up to 1400 MPa. This makes it perfect for high-stress rotating parts like turbine discs and wellhead shafts. 2.4856 (NiCr22Mo9Nb) is a solid-solution strengthened alloy that has much better corrosion resistance in harsh corrosive environments, such as seawater, strong acids and phosphoric acid, but its strength is noticeably lower. To put it simply, pick 2.4668 if you need the best mechanical performance, and choose 2.4856 if you require the highest level of corrosion resistance.

What mill test certificates do you provide with 2.4668 forgings?

All 2.4668 (NiCr19Fe19Nb5Mo3) forged parts come withEN 10204 Type 3.1 Mill Test Certificates as standard, issued by our in-house laboratory. EN 10204 Type 3.2, signed by a third-party inspection agency approved by you, is available upon request. These documents include chemical composition analysis, mechanical test results including tensile strength and hardness, heat treatment records, dimensional inspection reports, and NDT reports such as UT, MT and PT. We store all production records for at least 15 years after delivery.

Contact Jiangsu Liangyi for Custom 2.4668 Forging Solutions

As a leading manufacturer of 2.4668 (NiCr19Fe19Nb5Mo3) nickel superalloy forgings based in China, we provide full custom open die forging solutions from raw material melting to machining. Whether you need standard forged bars and rings or custom parts, we can supply high-quality products at competitive prices with on-time global delivery.

Inquiry Email: sales@jnmtforgedparts.com

Phone / WhatsApp: +86-13585067993

Official Website: www.jnmtforgedparts.com

Factory Address: Chengchang Industry Park, Jiangyin City, Jiangsu Province, China 214400

Welcome to send your custom drawings, material specifications, and quantity requirements to our sales team for a detailed, no-obligation quotation. Our technical team will work with you to optimize your forging design for cost and performance.