A Cast UNS N04020 Nickel-Copper Alloy,Cast UNS N04020; 1

### **Product Introduction: A Cast UNS N04020 (M-35-2) Nickel-Copper Alloy** **Overview** Cast UNS N04020, commonly known by its trade name **MONEL® alloy 400** in its wrought form and cast grade **M-35-2**, is a nickel-copper alloy renowned for its excellent corrosion resistance in a wide range of environments. It offers high strength and toughness over a broad temperature spectrum, from cryogenic levels up to about 480°C (900°F). This alloy is particularly celebrated for its exceptional performance in seawater and other corrosive saline media, resistance to caustic alkalies, and its overall robustness in the face of various corrosive conditions encountered in marine, chemical, and hydrocarbon processing industries. --- #### **Chemical Composition (Typical % by Weight, per ASTM A494)** The composition of M-35-2 is a simple yet highly effective solid-solution of nickel and copper. | Element | Content (%) | Role & Benefit | | :--- | :--- | :--- | | **Nickel (Ni)** | 63.0 min (inc. Co) | Forms the primary matrix, providing inherent corrosion resistance, ductility, and strength. | | **Copper (Cu)** | 28.0 - 34.0 | Imparts excellent resistance to reducing environments, sulfuric acid, and seawater corrosion. Synergizes with nickel for overall performance. | | **Iron (Fe)** | 2.5 max | A controlled residual element; kept low to optimize corrosion resistance in specific media. | | **Manganese (Mn)**| 1.5 max | Aids in castability, acts as a deoxidizer, and helps control sulfur. | | **Carbon (C)** | 0.35 max | A residual element from the manufacturing process. | | **Silicon (Si)** | 1.25 max (0.50 max for QQ-N-288) | A deoxidizer used in the casting process; content is controlled based on specification. | | **Sulfur (S)** | 0.025 max | A detrimental element kept to a minimum to prevent hot cracking and maintain ductility. | *Note: "MONEL" is a registered trademark of Special Metals Corporation.* --- #### **Physical & Mechanical Properties (Typical)** | Property | Value / Condition | | :--- | :--- | | **Density** | 8.80 g/cm³ (0.318 lb/in³) | | **Melting Range** | 1300 - 1350 °C (2370 - 2460 °F) | | **Specific Heat** | 427 J/kg·K (0.102 BTU/lb·°F) @ 20°C | | **Thermal Conductivity**| 22 W/m·K (152 BTU·in/hr·ft²·°F) @ 100°C | | **Thermal Expansion** | 13.9 μm/m·°C (7.7 μin/in·°F) @ 20-100°C | | **Tensile Strength** | 483 MPa (70 ksi) min | | **Yield Strength (0.2% Offset)** | 241 MPa (35 ksi) min | | **Elongation** | 25% min | --- #### **International Standards and Specifications** This cast nickel-copper alloy is recognized by several key international and military standards. * **Cast Product Standards:** * **ASTM A494 / A494M:** Standard Specification for Castings, Nickel and Nickel Alloy. (Grade M-35-2) * **UNS N04020:** Unified Numbering System designation for the cast alloy. * **Military QQ-N-288 Grade A:** U.S. military specification for castings. * **ASME SB-369:** Standard for Copper-Nickel Alloy Castings, which also covers this material. * **Wrought Equivalent:** * **UNS N04400 (MONEL 400):** The standard wrought form (e.g., plate, sheet, tube, bar). * **ASTM B164 / B165 / B127:** Standards for Nickel-Copper Alloy rod, bar, wire, seamless pipe and tube, and plate, sheet, and strip. --- #### **Product Applications** M-35-2 cast components are widely used in demanding marine and chemical processing applications. 1. **Marine & Offshore:** * Pump and valve components (casings, impellers, stems) for seawater handling. * Propeller shafts, marine fixtures, and fasteners. * Heat exchanger components and condenser plates. 2. **Chemical and Hydrocarbon Processing:** * Pumps and valves for handling chlorinated solvents, fluorine, and other chemicals. * Process vessels and piping for production and transportation of hydrocarbons. * Components exposed to caustic alkalies. 3. **Power Generation:** * Feedwater heater tubes, condenser tubes, and other components in power plants, particularly those using brackish or seawater for cooling. 4. **Other Industries:** * Crude oil stills, gasoline and freshwater tanks. #### **Key Advantages** * **Excellent Corrosion Resistance:** Superior performance in seawater, hydrofluoric acid, sulfuric acid, and alkalies. Highly resistant to chloride-ion stress-corrosion cracking. * **Good Mechanical Properties:** Maintains high strength and toughness from sub-zero temperatures to moderately high temperatures. * **Ease of Fabrication:** Can be readily welded and machined, allowing for the manufacture of complex cast components. * **Proven Track Record:** Decades of successful service in some of the most corrosive industrial and marine environments. **Conclusion** Cast UNS N04020 (M-35-2) is a time-tested and highly reliable nickel-copper alloy that delivers consistent performance in corrosive environments, particularly those involving seawater, acids, and alkalies. Its straightforward chemistry, combined with robust mechanical properties and excellent fabricability, makes it a first-choice material for critical components in marine, chemical, and energy sectors. Backed by international standards like ASTM A494 and military specifications like QQ-N-288, M-35-2 castings offer a proven solution for durability and long service life.

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 3404 gallon liquid totes Special package is available on request.