Exotic Alloys Alloy 254 Fasteners Overview
Zeon Exports supplies Exotic Alloy 254 (254 SMO, UNS S31254) fasteners – bolts, nuts and studs – a super austenitic 6% molybdenum stainless steel with a PREN of 42-44, developed for seawater and other aggressive chloride-bearing bolted joints.
Exotic Alloy 254 (254 SMO) Fasteners secure bolted connections in seawater and other aggressive chloride-bearing piping and equipment. Its 20% chromium, 18% nickel and 6% molybdenum composition with added nitrogen gives a PREN of 42-44, providing performance approaching nickel-based alloys while retaining the fabricability of stainless steel.
- PREN 42–44, roughly double the pitting resistance of 316L
- Tensile ≥650 MPa, yield ≥300 MPa in the annealed condition
- EN 10204 3.1 certified, export-ready worldwide
Quick Specifications of Exotic Alloys Alloy 254 Fasteners
Exotic Alloy 254 (254 SMO) Fasteners are produced to internationally recognized bolting specifications.
| Field | Detail |
|---|---|
| Material/Grade | Exotic Alloy 254 (254 SMO) |
| UNS | S31254 |
| DIN/Werkstoff Number | 1.4547 |
| Standards | ASTM A479, ASTM A276 |
| Form | Bolts, Nuts, Studs |
| Finish | As specified (confirm on order) |
| Heat Treatment | Solution Annealed |
| Certification | EN 10204 3.1 |
Equivalent Grades of Alloy 254
Alloy 254 (254 SMO) is recognized under several international designations below.
| UNS | DIN/Werkstoff Number | Common Trade Name | ASTM/ASME Standard |
|---|---|---|---|
| S31254 | 1.4547 | 254 SMO / 6Mo / F44 | ASTM A479 / A276 |
Chemical Composition of Alloy 254
Composition per ASTM A479/A276 for UNS S31254; exact limits can vary slightly by specification and heat.
| Element | Composition (%) |
|---|---|
| Chromium (Cr) | 19.5 – 20.5 |
| Nickel (Ni) | 17.5 – 18.5 |
| Molybdenum (Mo) | 6.0 – 6.5 |
| Nitrogen (N) | 0.18 – 0.22 |
| Copper (Cu) | 0.50 – 1.00 |
| Carbon (C), max | 0.020 |
| Manganese (Mn), max | 1.00 |
| Silicon (Si), max | 0.80 |
| Phosphorus (P), max | 0.030 |
| Sulphur (S), max | 0.010 |
| Iron (Fe) | Balance |
Physical Properties of Exotic Alloy 254 (254 SMO)
Typical physical properties for 254 SMO; confirm exact heat-specific figures against the mill test certificate.
| Property | Value |
|---|---|
| Density | ~8.0 g/cm3 (typical) |
| Melting Range | ~1320 – 1390°C (typical) |
| Magnetic Behaviour | Essentially non-magnetic |
Mechanical Properties of Exotic Alloys Alloy 254 Fasteners
Minimum mechanical properties for annealed UNS S31254 per ASTM A479/A276.
| Property | Minimum Value |
|---|---|
| Tensile Strength | 650 MPa (95 ksi) |
| Yield Strength (0.2% offset) | 300 MPa (44 ksi) |
| Elongation | 35% |
| Condition | Solution Annealed |
Corrosion Resistance of Exotic Alloy 254 (254 SMO)
- Exotic Alloy 254 Fasteners were developed specifically for seawater and other aggressive chloride environments.
- Pitting resistance: excellent resistance to chloride-induced pitting, roughly double that of 316L.
- Crevice resistance: high resistance to crevice corrosion in seawater, confirmed by ASTM G48 testing.
- Chloride SCC resistance: excellent resistance to chloride stress corrosion cracking, unlike standard austenitic grades.
Heat Resistance of Exotic Alloy 254 (254 SMO)
Exotic Alloy 254 fasteners retain excellent ductility and impact strength at both ambient and sub-zero temperatures; they are generally selected for moderate-temperature aqueous service rather than high-temperature structural applications. Confirm exact service limits against the governing standard and application before specifying.
Key Properties of Exotic Alloys Alloy 254 Fasteners
Beyond corrosion and heat performance, 254 SMO fasteners offer these additional properties.
- Strength roughly twice that of standard 300-series stainless steel
- Excellent weldability without preheating required
- Low carbon content minimizes carbide precipitation risk
- Good ductility and impact strength at sub-zero temperatures
Benefits of Exotic Alloys Alloy 254 Fasteners
Choosing 254 SMO fasteners from Zeon Exports delivers measurable advantages for your project.
- Nickel-alloy-level corrosion resistance at a lower cost
- Full MTC 3.1 documentation for project QA/QC requirements
- Multiple sizes, threads and finishes to match exact project specs
- Reliable bulk supply with consistent ready stock
- Competitive export pricing for large industrial orders
- Fast dispatch to global project sites and ports
Related Products
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Request a Quote for Exotic Alloys Alloy 254 Fasteners
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Call: +91 98205 33105
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Website: www.zeonexports.com
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Frequently Asked Questions About Exotic Alloys Alloy 254 Fasteners
Common questions about Exotic Alloy 254 (254 SMO) Fasteners, answered below.
Q1: What is Exotic Alloy 254 (254 SMO)?
Ans. 254 SMO (UNS S31254) is a super austenitic 6% molybdenum stainless steel with a PREN of 42-44.
Q2: Which fastener types are available in 254 SMO?
Ans. We supply bolts, nuts and studs manufactured to ASTM A479/A276 across standard thread sizes and lengths.
Q3: What standards do 254 SMO fasteners meet?
Ans. Fasteners are manufactured to ASTM A479/A276, certified to EN 10204 3.1 mill test certificates.
Q4: Is 254 SMO magnetic?
Ans. 254 SMO is essentially non-magnetic, being a fully austenitic stainless steel.
Q5: How does 254 SMO compare to 904L?
Ans. 254 SMO has higher molybdenum and nitrogen, giving a PREN of 42-44 versus 904L's PREN of around 34, for superior chloride pitting resistance.
Q6: Is 254 SMO suitable for seawater service?
Ans. Yes, 254 SMO was specifically developed for seawater and other aggressive chloride-bearing environments.
Q7: What certification is provided with orders?
Ans. Every order ships with EN 10204 3.1 mill test certificates confirming grade, heat and dimensions.
Q8: Does Zeon Exports supply custom sizes?
Ans. Yes, fasteners are available in custom thread sizes and lengths on request for bulk industrial orders.
