Inconel 718 FastenersUNS N07718 · Manufacturer, stockist & exporter, India
Also sold as Alloy 718 · UNS N07718 · W.Nr 2.4668 · Precipitation-hardening nickel alloy
Inconel 718 fasteners — stud bolts, hex bolts, nuts and washers — available in this alloy. ASTM A1014 (UNS N07718) where specified for applicable bolts and studs — product-type scope pending current standard text; for other types, material may be supplied to ASTM B637 bar where applicable, subject to the purchase specification or project drawing. Dimensions to ASME B18 where applicable, or your drawing. State the finished fastener specification your project requires on the order. It is a age-hardenable nickel–chromium alloy with niobium and molybdenum, chosen for very high strength at temperatures up to about 650 °C. Kanak Steel & Engineering Co. supplies it with EN 10204 3.1 mill certificates from Mumbai to buyers across India, the Gulf, South-East Asia, South America, Europe, the UK and the USA.
- Stock & mill supply
- EN 10204 3.1 / 3.2
- PMI on request
- NACE MR0175 on request
- Export packing
Reviewed by the Kanak Steel & Engineering Co. technical team · Updated October 2026
What is Inconel 718 Fasteners?
Inconel 718 fasteners is an age-hardenable nickel–chromium alloy with niobium and molybdenum supplied as fasteners (UNS N07718). ASTM A1014 (UNS N07718) where specified for applicable bolts and studs — product-type scope pending current standard text; for other types, material may be supplied to ASTM B637 bar where applicable, subject to the purchase specification or project drawing. Buyers specify it for very high strength at temperatures up to about 650 °C. It is also sold as Alloy 718, UNS N07718, W.Nr 2.4668.
- What it is
- Age-hardenable nickel–chromium alloy with niobium and molybdenum
- Material
- ASTM A1014 (UNS N07718) where specified for applicable bolts and studs — product-type scope pending current standard text; for other types, material may be supplied to ASTM B637 bar where applicable, subject to the purchase specification or project drawing
- Feedstock (bar)
- ASTM B637, where applicable
- Dimensions
- ASME B18.2.1 · B18.2.2 · B18.31.2
- Threads
- UNC · UN-8 · metric
- Sizes
- M10 – M64 · ½" – 4"
- Best at
- Very high strength at temperatures up to about 650 °C
Inconel 718 Fasteners Specification & Sizes
| Material | ASTM A1014 (UNS N07718) where specified for applicable bolts and studs — product-type scope pending current standard text; for other types, material may be supplied to ASTM B637 bar where applicable, subject to the purchase specification or project drawing |
|---|---|
| Material / feedstock | ASTM B637 — a bar specification, where applicable; it covers the bar, not the finished fastener |
| Manufacturing route | By type: bolts, studs, cap screws and nuts may be machined from bar, where applicable; threaded rod, U-bolts, eye bolts, anchor and foundation bolts are route-dependent; washers not asserted — all to the purchase specification or project drawing |
| Dimensional standards | ASME B18.2.1 (bolts) · B18.2.2 (nuts) · B18.31.2 (studs) · DIN 931 / 933 / 934 (legacy DIN) |
| Types | Stud bolt · Hex bolt · Heavy hex nut · Hex nut · Washer · Threaded rod · U-bolt · Eye bolt · Anchor bolt · Foundation bolt · Socket head cap screw · Machine screw |
| Threads | UNC, UN-8 and metric coarse |
| Coating | Plain · PTFE on request |
| Documents | EN 10204 3.1 |
Inconel 718 Stud Bolts: Grade & Nut Pairing
Inconel 718 studs and nuts may be machined from ASTM B637 bar, where applicable; the finished fastener specification is to the purchase specification or project drawing, and the nut is usually the same alloy. Bolting to ASTM A1014 is a precipitation-hardening bolting specification for UNS N07718 (product-type scope and property requirements pending current standard text); for bar ordered to aerospace specifications, AMS 5662 is the solution-treated and AMS 5663 the solution-treated-and-aged condition — state the condition on the order.
Torque (T = K × F × d), stud length and coatings are covered in the fasteners guide.
| Galling | Stainless and nickel-alloy threads gall — always use anti-seize, and avoid high-speed tightening |
|---|---|
| Coatings | Usually supplied plain; PTFE coating on request to ease tightening |
| Marking | Grade symbol and maker's mark on each stud end and nut, as the standard requires |
| Certificates | EN 10204 3.1 for the bar heat; mechanical test reports on the finished bolts on request |
Inconel 718 Fasteners Chemical Composition
| Element | Weight % (producer reference) |
|---|---|
| Nickel (+Co) | 50.00 – 55.00 |
| Chromium | 17.00 – 21.00 |
| Iron | Balance |
| Niobium (+Ta) | 4.75 – 5.50 |
| Molybdenum | 2.80 – 3.30 |
| Titanium | 0.65 – 1.15 |
| Aluminium | 0.20 – 0.80 |
| Cobalt | 1.00 max |
| Carbon | 0.08 max |
| Manganese | 0.35 max |
| Silicon | 0.35 max |
| Phosphorus | 0.015 max |
| Sulphur | 0.015 max |
| Boron | 0.006 max |
| Copper | 0.30 max |
Inconel 718 Fasteners Mechanical Properties
| Specification | Product form | Condition | Requirement values |
|---|---|---|---|
| ASTM A1014/A1014M (A1014/A1014M-26) | bolting (product types pending) | as specified | As specified |
Numerical requirements are not shown until the current edition of each standard has been verified. Mechanical properties depend on product form, size, condition and heat treatment — state them on the purchase order.
Density & Physical Properties
| Property | Value |
|---|---|
| Density | 8.19 g/cm³ |
| Melting range | 1260 – 1336 °C |
| Magnetic | Non-magnetic |
Typical / reference values (producer data, Special Metals SMC-045) — not specification requirements.
Inconel 718 Equivalent Grades
Values follow Special Metals INCONEL alloy 718 bulletin SMC-045 (2007) — producer reference composition, not a specification requirement; specification limits in ASTM B637-26, B670-25 and A1014/A1014M-26 are pending current standard text. Always check against the edition named on your purchase order.
Six-digit Harmonized System heading (nickel alloy, chapter 75). Your country adds its own digits — confirm with your customs broker. All HS codes.
How to Verify Inconel 718 Fasteners with PMI
Positive material identification with a handheld XRF gun confirms the alloy on the piece itself, in seconds, before it is cut or welded. Inconel 718 is most often mixed up with Inconel 625 — the table shows which elements tell them apart.
Handheld XRF does not measure carbon or nitrogen; those come from the mill certificate or optical emission (OES) testing. PMI can be arranged on request — state it on your enquiry.
Under technical review for TDS.
| Element | Inconel 718 (producer reference) | Inconel 625 |
|---|---|---|
| Nickel | 50.00 – 55.00 | As specified |
| Chromium | 17.00 – 21.00 | As specified |
| Molybdenum | 2.80 – 3.30 | As specified |
| Copper | 0.30 max | — |
| Titanium | 0.65 – 1.15 | As specified |
| Niobium | 4.75 – 5.50 | As specified |
| Iron | Balance | As specified |
| Manganese | 0.35 max | As specified |
Inconel 718 fasteners by type
Inconel 718 Fasteners Applications
Inconel 718 is specified when the cheaper grade will not survive the service but a higher alloy would be more than the job needs. These are the jobs our buyers use it for.
Inconel 718 Fasteners vs 625, 600 and 825
| Grade | Fasteners standard | PREN (approx.) | Pick it when |
|---|---|---|---|
| Inconel 600 | May be machined from ASTM B166 bar (UNS N06600), where applicable; finished fastener requirements are to the purchase specification or project drawing | — | High-temperature oxidation, caustic and nuclear service |
| Inconel 718 | ASTM A1014 (UNS N07718) where specified for applicable bolts and studs — product-type scope pending current standard text; for other types, material may be supplied to ASTM B637 bar where applicable, subject to the purchase specification or project drawing | — | Very high strength at temperatures up to about 650 °C |
| Inconel 825 | May be machined from ASTM B425 bar (UNS N08825), where applicable; finished fastener requirements are to the purchase specification or project drawing | ≈ 31 | Sulphuric and phosphoric acid service, chloride stress-corrosion cracking and sour gas |
| Inconel 625 | ASTM F468 (N06625) where specified for applicable bolts, hex cap screws, socket-head cap screws and studs (0.250–1.500 in.), and ASTM F467 for applicable nuts (0.250–1.500 in.); for other types, material may be supplied to ASTM B446 bar where applicable, subject to the purchase specification | ≈ 51 | Seawater, high strength and high temperature in one alloy |
PREN = Cr + 3.3 Mo + 16 N, from mid-range chemistry. A screening guide, not a substitute for corrosion data on your medium.
Inconel 718 Corrosion Resistance — Element by Element
Each alloying addition has a job. Knowing which one protects against your medium is the quickest way to judge whether 718 fits.
Niobium forms the gamma-double-prime precipitate that gives 718 its high strength after age hardening.
Keeps very high strength and creep resistance up to about 650 °C.
Its slow ageing response gives good resistance to strain-age cracking during post-weld heat treatment; welding procedure and post-weld treatment still follow the applicable code and specification.
718 is chosen for strength; for corrosion alone, 625 or 825 are usually better value.
How your 718 fasteners order runs
- 01Enquiry review — we confirm size, standard edition and documents against your MR or drawing.
- 02Heat selection & PMI — the mill certificate is checked against your order; PMI before processing is available on request.
- 03Processing — cutting, machining or bevelling to your specification, with heat numbers marked.
- 04Inspection — your third-party inspector witnesses, or we share photos and test reports.
- 05Packing & dispatch — seaworthy packing from Nhava Sheva (JNPT), Mumbai, FOB or CIF, documents sent before the vessel sails.
Welding & Fabricating Inconel 718 Fasteners
Inconel 718 welds by all common arc processes. A few points our buyers ask about:
| Matching filler | ERNiFeCr-2 (AWS A5.14) |
|---|---|
| Over-alloyed filler | Post-weld solution treatment and ageing restore strength |
| Preheat | Not required; keep interpass temperature low |
| Cutting | Thermal or abrasive cutting; grind off heat-tinted edges before welding |
Follow your approved WPS; this is general guidance. See also 718 fittings and 718 flanges for the matching pipe-system parts.
How to Order Inconel 718 Fasteners: RFQ Checklist
Get an accurate quote the first time. Copy this list into your enquiry:
- Fastener type, size and length
- Thread form
- Material and marking
- Quantity in sets
- Certificate type
- Delivery port and date
Inconel 718 fasteners for export
FOB / CIF · Nhava Sheva (JNPT), MumbaiTechnical documentation
A Kanak Steel technical data sheet for this product is being prepared. It is released as a PDF only after the current standard text, each value and its evidence, and a named technical reviewer have been confirmed — so no draft or placeholder sheet is offered for download.
Need technical data now? Send your enquiry with the standard and edition you are ordering to.
| Document | Inconel 718 — Fasteners technical data sheet |
|---|---|
| Document ID | KS-TDS-N07718-FS |
| Grade | Inconel 718 |
| UNS | N07718 |
| Product form | Fasteners (bolts and studs) |
| Standard | ASTM A1014 (current edition A1014/A1014M-26) |
| Status | Under technical review for TDS |
- Technical Data Sheet — Under technical review
Inconel 718 fasteners — questions buyers ask
Is Inconel 718 the same as Alloy 718?
Alloy 718, UNS N07718, W.Nr 2.4668 are names used for Inconel 718 (W.Nr / EN numbers and older UNS variants are the closest designations; their limits can differ slightly, so specify the UNS number and ASTM grade on the order). Whichever name is on the enquiry, fasteners: ASTM A1014 (UNS N07718) where specified for applicable bolts and studs — product-type scope pending current standard text.
Why use Inconel 718 bolts instead of B7 carbon steel?
On Inconel 718 flanges in corrosive service, carbon-steel bolts corrode first. Matching-alloy bolting avoids galvanic corrosion and bolt failure.
What nut goes with Inconel 718 stud bolts?
Usually a heavy hex nut in the same Inconel 718 alloy — it may be machined from ASTM B637 bar, where applicable; finished requirements are to the purchase specification or project drawing.
How do I stop Inconel 718 bolts galling?
Use an anti-seize compound on threads and nut faces, tighten at moderate speed, and do not reuse galled nuts.
Inconel 718 or Inconel 825 — which should I choose?
Inconel 718 is chosen for very high strength at temperatures up to about 650 °C. Inconel 825 is the step up when you need more pitting resistance or strength. See the comparison table on this page, or ask us with your process conditions.
Sources: the ASTM / ASME specifications named on this page and producer datasheets · Last updated October 2026