Buy Inconel 718 | Complete Specifications & Custom Processing

Sourcing precipitation-hardening nickel superalloys for aerospace turbines, sour-gas wellheads, or cryogenic pressure vessels requires more than a simple price check—it demands verified metallurgy, dimensional accuracy, and full traceability. Inconel 718 (UNS N07718 / W.Nr. 2.4668 / GH4169)​ is the industry benchmark for high-strength (≥1035 MPa yield), weldable Ni-Cr-Fe alloy operating from –253 °C to 650 °C. Shanghai COCESS Special Alloys Co., Ltd​ supplies aircraft- and NACE-grade Inconel 718 in bar, plate, seamless tube, and custom forgings, processed to ASTM B637, AMS 5662/5663, and AMS 5596, with EN 10204 3.1 certification and optional third-party inspection (SGS / TÜV / DNV).

Chemical Composition & Strengthening Mechanism

Inconel 718 is strengthened mainly by coherent γ" precipitates (Ni₃Nb) formed during aging, supported by γ' (Ni₃(Al,Ti)) and Mo solid-solution hardening. Strict control of C, S, and Nb is critical for hot workability and fatigue performance.

Typical Composition (wt%, per AMS 5662 / ASTM B637):

• Nickel (Ni):​ 50.00 – 55.00 % (Balance)

• Chromium (Cr):​ 17.00 – 21.00 % (Oxidation & general corrosion)

• Iron (Fe):​ 16.00 – 20.00 % (Austenite stabilizer)

• Niobium + Tantalum (Nb+Ta):​ 4.75 – 5.50 % (Primary γ" (Ni₃Nb) former → main age-hardener)

• Molybdenum (Mo):​ 2.80 – 3.30 % (Solid-solution strengthening, pitting resistance)

• Titanium (Ti):​ 0.65 – 1.15 %

• Aluminum (Al):​ 0.20 – 0.80 %

• Cobalt (Co):​ ≤ 1.00 %

• Carbon (C):​ ≤ 0.08 %

• Sulfur (S):​ ≤ 0.015 % (Tightly controlled to avoid hot cracking)

• Boron (B):​ ≤ 0.006 %

• Manganese (Mn):​ ≤ 0.35 %

• Silicon (Si):​ ≤ 0.35 %

Physical & Mechanical Data (Solution Treated + Aged)

Material is commonly supplied in solution-annealed (soft) condition for machining, then aged per standard two-step: 720 °C × 8h, furnace cool to 620 °C × 8h, air cool.

Physical Constants:

• Density:​ 8.19 – 8.24 g/cm³ (0.296 lb/in³)

• Melting Range:​ 1260 – 1336 °C (2300 – 2437 °F)

• Thermal Conductivity (21 °C):​ ~11.4 W/m·K

• Mean CTE (21–649 °C):​ ~14.6 × 10⁻⁶ /°C

• Curie Temp:​ < –196 °C (non‑magnetic in annealed state)

Room‑Temp Mechanical Minimums (AMS 5663 aged condition):

• Tensile Strength (Rm):​ ≥ 1275 MPa (185 ksi) — typical 1300–1380 MPa

• Yield Strength (Rp0.2):​ ≥ 1035 MPa (150 ksi) — typical 1100–1170 MPa

• Elongation (A5):​ ≥ 12–15 %

• Reduction of Area:​ ≥ 15–20 %

• Hardness:​ 331–401 HB (34–44 HRC)

Elevated Temp Reference (650 °C):

• Tensile Strength ≈ 965 MPa (140 ksi)

• Yield Strength ≈ 790 MPa (115 ksi)

• 100 h / 690 MPa Stress‑Rupture Life: typically ≥ 23 h

Available Product Forms & Custom Processing

We maintain wholesale-ready inventory and offer downstream processing to reduce your scrap and lead time:

Processing Services:

• Saw / abrasive cut to length

• Rough turning / facing / drill center hole

• Waterjet / CNC plasma profiling for plate

• Solution anneal & double‑step age (upon request)

• UT (per ASTM A388 / SEB 682), PT, MPI — optional

Key Advantages & Compliance

• NACE MR0175 / ISO 15156:​ Verified resistance to sulfide stress cracking (SSC) in H₂S/CO₂/Cl⁻ sour environments — qualified for downhole and Christmas‑tree components.

• Weldability:​ HAZ does not severely soften; post‑weld aging restores near‑base strength — ideal for large fabricated cases, ducts, and pressure vessels.

• Cryogenic to 650 °C Service:​ Tough at –253 °C (LOX/LH₂ systems) with retained strength to 650 °C — suitable for turbines, rocket engines, and subsea hardware.

• Full Traceability:​ Each shipment includes EN 10204 3.1 MTR (heat analysis + mechanical tests); 3.2 and third‑party witness available on request.

For current Inconel 718 stock lists, mill test report samples, or a quotation on bars, plates, tubes, or custom forgings, please contact Shanghai COCESS Special Alloys Co., Ltd. Our technical team can advise on heat‑treatment cycles, welding consumables (ERNiFeCr‑2), and NDT requirements to ensure your specification is met without compromise.

Website: https://en.cocessalloys.com
Email: sales@cocessalloys.com