Duplex Steel Screws are top-notch fastening components crafted from duplex stainless steel, which cleverly merges the benefits of both austenitic and ferritic structures. These screws are well-known for their remarkable strength, outstanding corrosion resistance, and impressive durability, making them perfect for tough environments. They stand out with their excellent resistance to pitting, crevice corrosion, and stress corrosion cracking, performing brilliantly in chloride-rich and marine settings. You’ll find Duplex Steel Screws widely used in engineering projects where secure fastening and a long service life are essential. Their strong mechanical properties and stability under high pressure and temperature make them incredibly reliable across various industrial applications
Duplex Steel Screws usually consist of chromium (21–23%), nickel (4.5–6.5%), molybdenum (2.5–3.5%), nitrogen, and a few trace elements that boost corrosion resistance and strength. Their balanced dual-phase microstructure provides high tensile strength, yield strength, and excellent toughness. They show remarkable resistance to chloride-induced corrosion and keep performing well even under changing thermal and mechanical loads. Plus, Duplex Steel Screws offer better fatigue resistance and lower thermal expansion compared to regular stainless steels, ensuring stability and reliability in demanding industrial environments.
| Standard | DIN, ASTM, BS and all International Standards |
| Specifications | ASTM A479 & ASME SA479 |
| UNS S32760 Nut and Bolts Size | M3 To M56 3/6″ to 2″ |
| Length | 3 to 200 MM |
| Super Duplex Steel 2207 Machine Screws Size | M1.6 To M12 |
| Duplex Steel 2205 Washers Size | M3 To M56 3/6″ to 2″ |
| Tensile Strength(MPa) min | Yield Strength 0.2% Proof (MPa) min | Elongation (% in 50mm) | Hardness Rockwell C (HR C) | |
| Super Duplex Steel Bolts | 760 | 550 | 15 | 32 Max |
| Phosphorus | Sulphur | Silicon | Carbon | Manganese | Nickel | Molybdenum | Nitrogen | Copper | Chromium |
|---|---|---|---|---|---|---|---|---|---|
| 0.035 % max | 0.02 % max | 0.80 % max | 0.03% Max | 1.20 % max | 6.00 – 8.00 % | 3.00 – 5.00 % | 0.24 – 0.32 % | 0.50 % max | 24.0 – 26.0 % |
| STANDARD | WERKSTOFF NR. | UNS |
| Hastelloy B2 | 2.4617 | N10665 |
Duplex Steel Screws are commonly found in industries that need secure fastening in highly corrosive or high-stress situations. They’re extensively used in petrochemical plants, offshore platforms, desalination units, chemical processing systems, and marine engineering. Their exceptional resistance to seawater corrosion makes them a go-to choice for shipbuilding and coastal projects. In construction and structural applications, they provide dependable fastening for heavy-duty components that face dynamic loads.
We provide products that come with both mill test certificates and third-party test certificates, ensuring the highest standards of quality and compliance.
