Duplex 2205 FastenersUNS S32205 · Manufacturer, trader & exporter, India
Also sold as UNS S32205 / S31803 · W.Nr 1.4462 · F51 / F60 · SAF 2205
Duplex 2205 fasteners — stud bolts, hex bolts, nuts and washers — available in this alloy. ASTM A1082 (S32205) where specified for applicable duplex bolts, studs, cap screws and nuts; for other types, material may be supplied to ASTM A276 / A479 bar where applicable, subject to the purchase specification. Dimensions to ASME B18 where applicable, or your drawing. State the finished fastener specification your project requires on the order. It is a duplex (austenitic-ferritic) stainless steel, chosen for strength with chloride resistance at a stainless-steel budget. Kanak Steel & Engineering Co. manufactures, trades and exports it from Mumbai; EN 10204 3.1 or 3.2 certificates are available on request / as specified in the PO. Markets we have supplied to include Oman, UAE, Saudi Arabia, Brazil, Argentina, Spain and Chile (India is the home market).
- Stock & mill supply
- EN 10204 3.1 / 3.2
- PMI on request
- Export packing
Reviewed by the Kanak Steel & Engineering Co. technical team · Updated October 2026
What is Duplex 2205 Fasteners?
Duplex 2205 fasteners is a duplex (austenitic-ferritic) stainless steel supplied as fasteners (UNS S32205). ASTM A1082 (S32205) where specified for applicable duplex bolts, studs, cap screws and nuts; for other types, material may be supplied to ASTM A276 / A479 bar where applicable, subject to the purchase specification. Buyers specify it for strength with chloride resistance at a stainless-steel budget. It is also sold as UNS S32205 / S31803, W.Nr 1.4462, F51 / F60.
- What it is
- Duplex (austenitic-ferritic) stainless steel
- Material
- ASTM A1082 (S32205) where specified for applicable duplex bolts, studs, cap screws and nuts; for other types, material may be supplied to ASTM A276 / A479 bar where applicable, subject to the purchase specification
- Feedstock (bar)
- ASTM A276 / A479, 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
- Strength with chloride resistance at a stainless-steel budget
Duplex 2205 Fasteners Specification & Sizes
| Material | ASTM A1082 (S32205) where specified for applicable duplex bolts, studs, cap screws and nuts; for other types, material may be supplied to ASTM A276 / A479 bar where applicable, subject to the purchase specification |
|---|---|
| Material / feedstock | ASTM A276 / A479 — 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 |
Duplex 2205 Stud Bolts: Grade & Nut Pairing
Duplex 2205 studs and nuts may be machined from ASTM A276 / A479 bar, where applicable; the finished fastener specification is to the purchase specification or project drawing, and the nut is usually the same alloy.
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 |
Duplex 2205 Fasteners Chemical Composition
Under technical review for TDS.
| Element | Current requirement |
|---|---|
| Chromium | As specified |
| Nickel | As specified |
| Molybdenum | As specified |
| Nitrogen | As specified |
| Carbon | As specified |
| Manganese | As specified |
| Silicon | As specified |
| Phosphorus | As specified |
| Sulphur | As specified |
| Iron | As specified |
Numerical specification requirements are published only after the applicable current standard edition has been verified. Governing specification to be verified: ASTM A240 for UNS S32205.
Duplex 2205 Fasteners Mechanical Properties
Under technical review for TDS.
| Property | Current requirement |
|---|---|
| Tensile strength | As specified |
| Yield strength 0.2% | As specified |
| Elongation | As specified |
| Hardness | As specified |
Numerical specification requirements are published only after the applicable current standard edition has been verified. Governing specification and condition to be verified: ASTM A240 for UNS S32205 — Solution-annealed plate & sheet.
Density & Physical Properties
| Property | Value |
|---|---|
| Density | 7.8 g/cm³ |
| Melting range | 1385 – 1445 °C |
| Magnetic | Magnetic (ferritic phase) |
| PREN (approx.) | ≈ 35 |
Duplex 2205 Equivalent Grades
Six-digit Harmonized System heading (iron and steel, chapter 72–73). Your country adds its own digits — confirm with your customs broker. All HS codes.
How to Verify Duplex 2205 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. Duplex 2205 is most often mixed up with Super Duplex 2507 — the table shows which elements tell them apart.
Handheld XRF does not measure carbon or nitrogen, so it cannot confirm the nitrogen that duplex depends on: that comes 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 | Duplex 2205 | Super Duplex 2507 |
|---|---|---|
| Nickel | As specified | As specified |
| Chromium | As specified | As specified |
| Molybdenum | As specified | As specified |
| Copper | — | As specified |
| Iron | As specified | As specified |
| Manganese | As specified | As specified |
Duplex 2205 fasteners by type
Duplex 2205 Fasteners Applications
Duplex 2205 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.
Duplex 2205 Fasteners vs 316L, 904L and 2507
| Grade | Fasteners standard | PREN (approx.) | Pick it when |
|---|---|---|---|
| SS 316 / 316L | ASTM A193 B8M · A194 8M | ≈ 24 | Chloride-bearing process fluids, marine air and pharmaceutical service |
| SS 904L | May be machined from ASTM A479 bar (UNS N08904), where applicable; finished fastener requirements are to the purchase specification or project drawing | ≈ 35 | Dilute sulphuric acid, phosphoric acid and chloride-bearing cooling water |
| Duplex 2205 | ASTM A1082 (S32205) where specified for applicable duplex bolts, studs, cap screws and nuts; for other types, material may be supplied to ASTM A276 / A479 bar where applicable, subject to the purchase specification | ≈ 35 | Strength with chloride resistance at a stainless-steel budget |
| Super Duplex 2507 | ASTM A1082 (S32750) where specified for applicable duplex bolts, studs, cap screws and nuts; for other types, material may be supplied to ASTM A276 / A479 bar where applicable, subject to the purchase specification | ≈ 42 | Seawater and high-chloride service where strength also matters |
PREN = Cr + 3.3 Mo + 16 N, from mid-range chemistry. A screening guide, not a substitute for corrosion data on your medium.
Duplex 2205 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 2205 fits.
A roughly 50/50 austenite-ferrite structure gives about twice the yield strength of 316L, so walls can be thinner.
Chromium, molybdenum and nitrogen give a PREN around 35 — well above 316L.
The ferrite phase gives far better resistance to chloride stress-corrosion cracking than austenitic grades.
Keep service below about 300 °C to avoid embrittlement.
How your 2205 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 can be arranged depending on product and requirements, as specified in the PO.
- 03Processing — cutting, machining or bevelling to your specification, with heat numbers marked as specified in the PO.
- 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.
Standards on this page
Welding & Fabricating Duplex 2205 Fasteners
Duplex 2205 welds by all common arc processes. A few points our buyers ask about:
| Matching filler | ER2209 (AWS A5.9) |
|---|---|
| Over-alloyed filler | Control heat input 0.5–2.5 kJ/mm to keep the phase balance |
| 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 2205 fittings and 2205 flanges for the matching pipe-system parts.
How to Order Duplex 2205 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
Technical 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 | Duplex 2205 — Fasteners technical data sheet |
|---|---|
| Document ID | KS-TDS-S32205-FS |
| Grade | Duplex 2205 |
| UNS | S32205 |
| Product form | Fasteners (bolting components) |
| Standard | ASTM A1082 (current edition A1082/A1082M-26) |
| Status | Under technical review for TDS |
- Technical Data Sheet — Under technical review
Duplex 2205 fasteners — questions buyers ask
Is Duplex 2205 the same as UNS S32205 / S31803?
UNS S32205 / S31803, W.Nr 1.4462, F51 / F60 are names used for Duplex 2205 (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 A1082 (S32205) where specified for applicable duplex bolts, studs, cap screws and nuts.
Why use Duplex 2205 bolts instead of B7 carbon steel?
On Duplex 2205 flanges in corrosive service, carbon-steel bolts corrode first. Matching-alloy bolting avoids galvanic corrosion and bolt failure.
What nut goes with Duplex 2205 stud bolts?
Usually a heavy hex nut in the same Duplex 2205 alloy — it may be machined from ASTM A276 / A479 bar, where applicable; finished requirements are to the purchase specification or project drawing.
How do I stop Duplex 2205 bolts galling?
Use an anti-seize compound on threads and nut faces, tighten at moderate speed, and do not reuse galled nuts.
Duplex 2205 or Super Duplex 2507 — which should I choose?
Duplex 2205 is chosen for strength with chloride resistance at a stainless-steel budget. Super Duplex 2507 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