Products
Min Temp
Max Temp
🌡
⚡
🛡
⚖
| Specification | Value |
|---|---|
| UNS Number | N08020 |
| ASTM/ASME Standard | ASTM B473 / B462 |
| Tensile Strength | 620 MPa (min) |
| Yield Strength | 240 MPa (min) |
| Density | 8.08 g/cm³ |
| Max Service Temperature | 760°C |
| Element | Composition (%) |
|---|---|
| Ni | 32.0–38.0 |
| Cr | 19.0–21.0 |
| Mo | 2.0–3.0 |
| Cu | 3.0–4.0 |
| Nb | 8×C min |
| Fe | bal |
| C | ≤0.07 |
| Mn | ≤2.0 |
Alloy 20 (Carpenter 20Cb-3) fasteners derive their exceptional performance from a carefully balanced composition of nickel, chromium, and molybdenum, stabilized with niobium (columbium). Nickel content of approximately 32-38% provides a stable austenitic structure and enhances resistance to chloride stress corrosion cracking, while chromium at 19-21% contributes to oxidation resistance and general corrosion protection. Molybdenum, present at 2-3%, significantly improves resistance to pitting and crevice corrosion, particularly in sulfuric acid environments. Copper addition, unique to this alloy, further boosts resistance to sulfuric acid attack. Niobium stabilizes the alloy against sensitization during welding, preventing intergranular corrosion.
These alloying elements combine to deliver outstanding resistance to sulfuric acid, phosphoric acid, and various chloride-containing media, making Alloy 20 fasteners ideal for chemical processing applications. The material maintains excellent mechanical strength and dimensional stability under demanding service conditions, resisting stress corrosion cracking where standard stainless steels fail. Its balanced composition ensures reliable performance in high-temperature acidic environments, supporting long-term structural integrity. These properties make Alloy 20 fasteners the preferred choice for pumps, valves, and piping systems in aggressive chemical processing industries.
Specifications
Alloy 20 (Carpenter 20Cb-3) Fasteners are specified by their corrosion-resistant mechanical properties, tensile performance, and precise dimensional tolerances, making them suitable for demanding industrial assemblies. Their technical data typically centers on strength, hardness, and size compatibility, with specifications defined by the required application and material standard.
| Property | Value |
|---|---|
| Tensile Strength | 620 MPa (min) |
| Yield Strength (0.2% offset) | 240 MPa (min) |
| Elongation | 30% (min) |
| Hardness | ≤ 90 HRB |
| Modulus of Elasticity | 193 GPa |
| Thermal Expansion (20-100°C) | 14.4 x10⁻⁶/°C |
| Thermal Conductivity | 12.4 W/m·K |
| Density | 8.08 g/cm³ |
| Melting Range | 1350-1400°C |
| Max Service Temperature | 760°C |
| Standard/Parameter | Details |
|---|---|
| Bolt Standard | ASME B18.2.1, DIN 931/933 |
| Stud Bolt Standard | ASME B16.5, MSS SP-75 |
| Nut Standard | ASME B18.2.2, DIN 934 |
| Washer Standard | ASME B18.22.1, DIN 125 |
| Thread Form | UNC, UNF, Metric Coarse |
| Diameter Range | M6 - M100 (1/4" - 4") |
| Length Range | 10mm - 500mm |
| Available Product Forms | Bolts, Studs, Nuts, Washers, Screws |
| Custom Sizes | Available on request |
| Manufacturing Standards | ASTM B473, ASTM B462 |
Applications
