CW-12MW Cast UNS N30002 Severe Corrosion and Heat Resistant Alloy,，1

### **Product Introduction: CW-12MW (Cast UNS N30002) Severe Corrosion and Heat Resistant Alloy** **Overview** CW-12MW, also known by its unified numbering system designation UNS N30002, is a nickel-molybdenum-chromium-iron-tungsten casting alloy designed to deliver exceptional resistance to severe corrosive environments. It is the cast equivalent of the widely used wrought alloy UNS N10276 (Hastelloy® C-276). This alloy maintains excellent corrosion resistance in both oxidizing and reducing media, and exhibits superior performance in applications involving high temperatures, chlorides, and strong acids, particularly where pitting, crevice corrosion, and stress corrosion cracking are concerns. Its unique chemical composition provides a robust solution for the most demanding applications in chemical processing, pollution control, and pulp and paper production. --- #### **Chemical Composition (Typical % by Weight, per ASTM A494)** The balanced composition of CW-12MW is key to its performance: | Element | Content (%) | Role & Benefit | | :--- | :--- | :--- | | **Nickel (Ni)** | Balance | Provides inherent corrosion resistance and ductility. Forms the matrix of the alloy. | | **Molybdenum (Mo)** | 15.0 - 17.0 | Imparts exceptional resistance to reducing acids (e.g., HCl, H₂SO₄) and pitting/crevice corrosion. | | **Chromium (Cr)** | 14.5 - 16.5 | Provides resistance to oxidizing media (e.g., HNO₃, Fe³⁺, Cu²⁺, hypochlorite) and high-temperature oxidation. | | **Iron (Fe)** | 4.0 - 7.0 | Balances the structure and helps control cost. | | **Tungsten (W)** | 3.0 - 4.5 | Enhances resistance to reducing acids and pitting corrosion, acting synergistically with Molybdenum. | | **Carbon (C)** | 0.01 max | Kept low to minimize carbide precipitation, which can sensitize the alloy and reduce corrosion resistance in weld zones. | | **Silicon (Si)** | 1.00 max | A deoxidizer used in the casting process. | | **Manganese (Mn)**| 1.00 max | Aids in castability and controls sulfur content. | | **Vanadium (V)** | 0.35 max | Typically a residual element from the manufacturing process. | | **Phosphorus (P)**| 0.04 max | Kept low to ensure good ductility and toughness. | | **Sulfur (S)** | 0.03 max | A detrimental element kept to a minimum to prevent hot cracking and maintain ductility. | | **Cobalt (Co)** | 2.50 max | Typically a residual element. | *Note: "Hastelloy®" is a registered trademark of Haynes International Inc.* --- #### **Physical & Mechanical Properties (Typical)** | Property | Value / Condition | | :--- | :--- | | **Density** | 8.89 g/cm³ (0.321 lb/in³) | | **Melting Range** | 1323 - 1371 °C (2413 - 2500 °F) | | **Specific Heat** | 427 J/kg·K (0.102 BTU/lb·°F) @ 20°C | | **Thermal Conductivity**| 11.1 W/m·K (77 BTU·in/hr·ft²·°F) @ 100°C | | **Thermal Expansion** | 11.2 μm/m·°C (6.2 μin/in·°F) @ 20-100°C | | **Tensile Strength** | 586 MPa (85 ksi) min | | **Yield Strength (0.2% Offset)** | 241 MPa (35 ksi) min | | **Elongation** | 4.5% min | --- #### **International Standards and Specifications** CW-12MW is recognized and specified by several major international standards organizations, ensuring consistent quality and performance. * **Cast Product Standards:** * **ASTM A494 / A494M:** Standard Specification for Castings, Nickel and Nickel Alloy. (Grade CW-12MW) * **UNS N30002:** Unified Numbering System designation for the cast alloy. * **ISO 15156-3 (MR0175):** This alloy is acceptable for use in sour service (H₂S-containing) environments as per NACE MR0175/ISO 15156. * **Wrought Equivalent:** * **UNS N10276:** The standard wrought form of this alloy (e.g., plate, sheet, tube, bar). * **ASTM B574:** Standard Specification for Low-Carbon Nickel-Molybdenum-Chromium Alloy Rod, Bar, and Wire. * **ASTM B575:** Standard Specification for Low-Carbon Nickel-Molybdenum-Chromium Alloy Plate, Sheet, and Strip. * **DIN 2.4819:** The corresponding material number in the German standard. --- #### **Product Applications** CW-12MW cast components are critical in industries where standard stainless steels and other nickel alloys fail. Typical applications include: 1. **Chemical Processing Industry (CPI):** * Reactors, vessels, and columns for the production of acetic acid, cellulose, and other aggressive chemicals. * Pumps, valves, and impellers handling hydrochloric acid, sulfuric acid, and chlorine gas. * Heat exchangers and piping systems in corrosive service. 2. **Pollution Control & Flue Gas Desulfurization (FGD):** * Scrubbers, ducting, fan housings, and dampers that resist the corrosive attack from sulfurous and chlorinated gases in power plant and incinerator emissions. 3. **Pulp and Paper Industry:** * Digesters, bleach washers, and stock lines where chlorides and oxidizing bleaching agents are present. 4. **Pharmaceutical Industry:** * Process equipment requiring high purity and resistance to cleaning agents and process streams. 5. **Waste Treatment:** * Components in systems that process mixed chemical wastes. #### **Key Advantages** * **Exceptional Versatility:** Resists a wider range of corrosives than most other nickel-based alloys, handling both oxidizing and reducing conditions. * **Superior Localized Corrosion Resistance:** Excellent resistance to pitting and crevice corrosion in chloride-containing solutions. * **Out-of-Service Performance:** The low carbon content and balanced chemistry make it highly resistant to sensitization and subsequent intergranular attack in the as-welded or as-cast condition. * **High-Temperature Stability:** Maintains good mechanical strength and oxidation resistance at elevated temperatures. **Conclusion** CW-12MW (UNS N30002) is a premier, heavy-duty corrosion-resistant casting alloy designed for the most challenging industrial environments. Its proven performance, backed by international standards like ASTM A494, makes it the material of choice for critical components where equipment failure is not an option, ensuring long service life, safety, and operational reliability.

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 3392 gallon liquid totes Special package is available on request.