Alloy 20 / 020，Carpenter 20Cb-3 Sheet，UNS N08020,E FORU

British Specs:，American Specs:，German Specs: WS 2.4660

**Product Name:** Alloy 20 / Carpenter 20Cb-3® Sheet | UNS N08020 **Material Type:** Nickel-Iron-Chromium Austenitic Stainless Steel Sheet **Standard:** ASTM B463, ASME SB463, ASTM A480 --- ### **Overview** Alloy 20 Sheet (UNS N08020), commercially known as **Carpenter 20Cb-3®**, is a nickel-iron-chromium austenitic stainless steel sheet specifically developed for superior resistance to sulfuric acid corrosion and other aggressive chemical environments. This sheet product combines exceptional corrosion resistance with excellent formability and weldability, making it ideal for fabricating chemical processing equipment, storage tanks, and various industrial components exposed to corrosive media. --- ### **Key Advantages** - **Exceptional Sulfuric Acid Resistance:** Optimized performance across all sulfuric acid concentrations - **Superior Chloride Resistance:** Excellent resistance to stress corrosion cracking - **Enhanced Fabricability:** Excellent forming and welding characteristics - **Good Mechanical Properties:** Balanced strength and ductility - **Stabilized Chemistry:** Niobium prevents sensitization during welding - **Cost-Effective Solution:** Long service life reduces maintenance costs --- ### **Chemical Composition (Typical Weight %)** | Element | Content (%) | Element | Content (%) | |---------|-------------|---------|-------------| | Nickel (Ni) | 32.0-38.0 | Chromium (Cr) | 19.0-21.0 | | Iron (Fe) | Balance | Molybdenum (Mo) | 2.0-3.0 | | Copper (Cu) | 3.0-4.0 | Manganese (Mn) | ≤2.0 | | Silicon (Si) | ≤1.0 | Carbon (C) | ≤0.07 | | Niobium (Nb) | 8×C-1.0 | Phosphorus (P) | ≤0.045 | | Sulfur (S) | ≤0.035 | | | --- ### **Physical & Mechanical Properties** #### **Physical Properties** - **Density:** 8.08 g/cm³ (0.292 lb/in³) - **Melting Range:** 1440-1500°C (2620-2730°F) - **Thermal Expansion Coefficient:** 15.9 × 10⁻⁶/°C (20-100°C) - **Modulus of Elasticity:** 186 GPa (27 × 10⁶ psi) - **Thermal Conductivity:** 12.9 W/m·K at 100°C - **Electrical Resistivity:** 0.90 μΩ·m at 20°C #### **Mechanical Properties (Annealed Condition)** | Property | Typical Value | |----------|---------------| | Tensile Strength | 620-690 MPa (90-100 ksi) | | Yield Strength (0.2% Offset) | 300-415 MPa (44-60 ksi) | | Elongation in 2" | 30-50% | | Hardness | 150-190 HB | | Shear Strength | 370-415 MPa (54-60 ksi) | --- ### **Product Specifications** #### **Sheet Specifications** - **Thickness Range:** 0.5 mm to 6.0 mm (0.020" to 0.250") - **Width Range:** 24" to 60" (600 mm to 1500 mm) - **Length:** Standard 96" to 240" (2400 mm to 6000 mm) - **Surface Finish:** 2B, No. 1, BA, or as specified - **Condition:** Solution Annealed and Pickled #### **Standard Specifications** - **ASTM B463:** UNS N08020 Sheet, Plate, and Strip - **ASME SB463:** Sheet for ASME Code Applications - **ASTM A480:** General Requirements for Flat Products #### **Available Conditions** - Hot Rolled, Annealed and Pickled - Cold Rolled, Annealed and Pickled - Solution Annealed - Stress Relieved --- ### **International Standards & Certifications** - **UNS:** N08020 - **ASTM/ASME:** B463/SB463 - **EN:** 10088-2 (Material No. 2.4660) - **ISO:** 9443 (Tolerances for Stainless Steel Sheet) - **Certifications:** NACE MR0175, PED 2014/68/EU, ISO 15156 --- ### **Applications** #### **Chemical Processing Industry** - Sulfuric acid pickling tanks and linings - Chemical processing equipment panels - Storage tank construction - Ductwork for corrosive fume handling - Reactor vessel linings #### **Pharmaceutical Industry** - Process equipment fabrication - Clean room components - Pharmaceutical storage containers - Processing table surfaces #### **Food Processing** - Vinegar production equipment - Acid food processing machinery - Pickle processing equipment - Food grade acid storage #### **Industrial Applications** - Pollution control equipment - Scrubber system components - Heat exchanger panels - Industrial chemical containers --- ### **Fabrication Characteristics** #### **Forming Operations** - **Deep Drawing:** Excellent capabilities - **Bending:** Minimum bend radius 1-2 times thickness - **Roll Forming:** Suitable for all standard operations - **Stretch Forming:** Good elongation characteristics #### **Welding Procedures** - **Recommended Methods:** GTAW, GMAW, Resistance Welding - **Filler Metals:** Alloy 20, ERNiCrFe-11 - **Shielding Gas:** 100% Argon for GTAW - **Heat Input:** Moderate to low recommended #### **Cutting & Machining** - **Shearing:** Clean edges achievable - **Plasma Cutting:** Recommended for precise cuts - **Laser Cutting:** Excellent results - **Machining:** Use positive rake tools with coolant --- ### **Corrosion Resistance** #### **Chemical Resistance** - **Excellent:** Sulfuric acid (all concentrations to 95°C) - **Good:** Phosphoric acid, nitric acid, organic acids - **Resistant:** Chloride stress corrosion cracking - **Limited:** Hydrochloric acid, hydrofluoric acid #### **Special Features** - Copper content enhances sulfuric acid resistance - Niobium stabilization prevents intergranular corrosion - Balanced composition for wide corrosion resistance - Superior to 316L in chloride environments --- ### **Quality Assurance** #### **Testing & Inspection** - Chemical analysis certification - Mechanical property testing - Corrosion testing per ASTM A262 - Surface quality inspection - Dimensional verification #### **Certification** - Mill test certificates to EN 10204 3.1/3.2 - Full material traceability - NACE MR0175/ISO 15156 compliance - PED certification available --- ### **Design Considerations** #### **Allowable Stresses** | Temperature (°C) | Maximum Allowable Stress (MPa) | |------------------|-------------------------------| | -29 to 38 | 138 | | 100 | 138 | | 150 | 128 | | 200 | 119 | | 250 | 111 | #### **Fabrication Tips** - Maintain clean working environment - Use dedicated tools for nickel alloys - Avoid carbon steel contamination - Proper storage to prevent surface damage --- ### **Conclusion** Alloy 20/Carpenter 20Cb-3® Sheet provides an outstanding combination of corrosion resistance, formability, and fabrication versatility for handling aggressive chemical environments. Its superior performance in sulfuric acid and chloride-containing media, combined with excellent mechanical properties and ease of fabrication, makes it the material of choice for chemical processing equipment, storage tanks, and industrial components. The sheet form offers manufacturers and fabricators a reliable, cost-effective solution for constructing durable equipment that ensures long-term performance in the most demanding corrosive applications. --- *Carpenter 20Cb-3® is a registered trademark of Carpenter Technology Corporation. All technical data are typical values and should be verified for specific applications. Consult manufacturer's specifications for project-specific requirements.*

Packing of Standard Packing: Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and steel drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 2670 gallon liquid totes Special package is available on request.