UNS N08020( Alloy 20)
Generic Name & Other Designation
Carpenter® 20Cb-3®, Alloy 20, 20CB-3, W.Nr. 2.4660
Product Overview
UNS N08020 (Alloy 20) is a niobium-stabilized austenitic iron-nickel-chromium alloy tailored specifically to overcome severe sulfuric acid corrosion encountered in chemical processing. Containing significant additions of copper and molybdenum, UNS N08020 provides robust defense against general corrosion, pitting, and crevice attack in aggressive acidic solutions.
It is widely utilized in chemical mixing tanks, pickling systems, and food processing lines handling organic and inorganic acid media.
Key Highlights
✅ Sulfuric Acid Benchmark: Specifically optimized for hot sulfuric acid environments from 20% to 40% concentration.
✅ Niobium Stabilization: Niobium alloying eliminates carbide precipitation during welding operations.
✅ Stress Corrosion Resistance: High nickel matrix shields against chloride-induced stress corrosion cracking.
✅ Cost-Effective Alloy: Delivers higher performance than 316L stainless at a manageable cost point.
Chemical Composition & Physical Properties
- 1.Chemical Composition (wt%)
Element | Ni | Cr | Fe | Cu | Mo | Nb (+Ta) | Mn | Si | C | P | S |
Min (%) | 32.0 | 19.0 | Bal. | 3.0 | 2.0 | 8×C | — | — | — | — | — |
Max (%) | 38.0 | 21.0 | (~40.0) | 4.0 | 3.0 | 1.00 | 2.0 | 1.00 | 0.07 | 0.045 | 0.035 |
2. Physical & Mechanical Properties
Parameter | Value / Standard (Annealed State) |
Density | 8.05 g/cm³ (0.291 lb/in³) |
Melting Range | 1350°C – 1440°C (2460°F – 2620°F) |
Tensile Strength (Rm) | ≥ 550 MPa (80 ksi) |
Yield Strength (0.2%, Rp0.2) | ≥ 240 MPa (35 ksi) |
Elongation (A5) | ≥ 30% |
Hardness Range | ≤ 217 HBW (95 HRB) |
Available Forms
Piping & Tubing: ASTM B464 / B729 / B468; Seamless & welded process pipes, hydraulic control tubing.
Bar & Rod Stock: ASTM B473 / ASME SB473; Hot-rolled round bars, forged rods, and cold-drawn wire stock.
Plates & Sheets: ASTM B463 / ASME SB463; Tank wall plates, clad backings, and filter sheets (0.5mm to 50mm).
Valves & Pipe Fittings: ASTM B462 / ASTM B366; Pump casings, flange rings, threaded elbows, and tees.
Welding Consumables: Compatible filler metals (AWS A5.14 ERNiCrMo-11 / AWS A5.11 ENiCrMo-11 / ER320LR).
Typical Application Scenarios
Chemical Synthesis: Sulfuric acid production lines, pickling tanks, synthetic rubber processing.
Pharmaceuticals: Mixing tanks, process reactors, acid metering lines.
Food & Beverage: Processing systems handling hot organic acids and CIP chemicals.
Quality Assurance & Testing
Intergranular corrosion resistance verified per ASTM A262 Practice E.
Hydrostatic testing and non-destructive examination (NDE) on pipe products.
Supplied with mill certification matching EN 10204 3.1 standards.
Supplier Information (BELNADE)
BELNADE is a key distributor of UNS N08020 products. BELNADE provides seamless supply chain management, custom cutting, and tailored packaging to meet global industrial demands.
Get in Touch with BELNADE for Quotes and Technical Inquiries
📧 Email: info@belnade-material.com
🌐 Website: www.belnade-material.com
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