HP Alloys Alloy C-276，1

### **Product Introduction: HP Alloys Alloy C-276 - Nickel-Chromium-Molybdenum Superalloy** **Overview** HP Alloys Alloy C-276 is a nickel-chromium-molybdenum-tungsten superalloy renowned for its exceptional corrosion resistance in the most severe environments. This versatile alloy demonstrates outstanding performance in both oxidizing and reducing media, offering superior resistance to pitting, crevice corrosion, and stress corrosion cracking. With its low carbon content and optimized chemical composition, Alloy C-276 maintains excellent structural stability and corrosion resistance in as-welded conditions, making it an ideal choice for demanding applications across chemical processing, pollution control, and industrial sectors. --- #### **Chemical Composition (Typical % by Weight)** | Element | Content (%) | Role & Benefit | |---------|-------------|---------------| | **Nickel (Ni)** | Balance | Forms corrosion-resistant matrix and provides fundamental stability | | **Chromium (Cr)** | 14.5 - 16.5 | Imparts resistance to oxidizing media and high-temperature corrosion | | **Molybdenum (Mo)** | 15.0 - 17.0 | Provides exceptional resistance to reducing acids and localized corrosion | | **Tungsten (W)** | 3.0 - 4.5 | Enhances resistance to reducing environments and pitting corrosion | | **Iron (Fe)** | 4.0 - 7.0 | Balances microstructure and provides cost-effectiveness | | **Cobalt (Co)** | 2.5 max | Controlled residual element | | **Manganese (Mn)** | 1.0 max | Aids in manufacturability and process control | | **Vanadium (V)** | 0.35 max | Trace element for process optimization | | **Silicon (Si)** | 0.08 max | Kept low to maintain corrosion resistance | | **Carbon (C)** | 0.01 max | Minimized to prevent sensitization and intergranular attack | | **Phosphorus (P)** | 0.04 max | Controlled for optimal properties | | **Sulfur (S)** | 0.03 max | Minimized to prevent hot cracking | *Note: This alloy corresponds to UNS N10276/W.Nr. 2.4819/Hastelloy C-276* --- #### **Physical & Mechanical Properties** **Physical Properties:** - Density: 8.89 g/cm³ (0.321 lb/in³) - Melting Range: 1323-1371°C (2413-2500°F) - Thermal Expansion: 11.2 μm/m·°C @ 20-100°C - Thermal Conductivity: 11.1 W/m·K @ 100°C - Specific Heat Capacity: 427 J/kg·K @ 20°C - Modulus of Elasticity: 205 GPa (29.7 x 10⁶ psi) - Magnetic Permeability: Essentially non-magnetic **Mechanical Properties (Annealed Condition):** - Tensile Strength: 690 MPa (100 ksi) minimum - Yield Strength (0.2% Offset): 283 MPa (41 ksi) minimum - Elongation: 40% minimum - Hardness: HRB ≤ 100 - Impact Strength: ≥ 135 J @ 20°C **Elevated Temperature Properties:** - Excellent mechanical properties up to 400°C (750°F) - Good creep and stress rupture strength - Maintains corrosion resistance at high temperatures --- #### **International Standards and Specifications** - **ASTM B574:** Low-Carbon Nickel-Molybdenum-Chromium Alloy Rod and Bar - **ASTM B575:** Low-Carbon Nickel-Molybdenum-Chromium Alloy Plate, Sheet, and Strip - **ASTM B622:** Nickel Alloy Seamless Pipe and Tube - **ASME SB-574/SB-575/SB-622:** Pressure vessel applications - **AMS 5754:** Aerospace Material Specification - **NACE MR0175/ISO 15156:** Sour service compliance - **EN 2.4819:** European material designation - **DIN 17744:** Wrought nickel and nickel alloy sheet, strip and plate --- #### **Product Applications** **Chemical Processing Industry:** - Reactors and pressure vessels for aggressive chemical production - Heat exchangers and condensers in corrosive service - Pumps, valves, and fittings for acid handling - Mixing tanks and agitators for corrosive media - Distillation columns and absorption towers **Pollution Control Systems:** - Flue gas desulfurization (FGD) systems - Scrubbers and absorbers for acid gas removal - Waste water treatment equipment - Chemical waste incineration systems - Air pollution control equipment **Pulp and Paper Industry:** - Digester and bleach plant equipment - Chemical recovery systems - Process piping and storage vessels - Black liquor handling equipment **Pharmaceutical Industry:** - Process equipment requiring high purity - Reaction vessels and purification systems - Critical component manufacturing - High-purity chemical synthesis --- #### **Key Advantages** 1. **Exceptional Corrosion Resistance**: Outstanding performance in diverse corrosive environments including acids, chlorides, and oxidizing media 2. **Versatile Application Range**: Suitable for both oxidizing and reducing conditions 3. **Superior Localized Corrosion Resistance**: Excellent resistance to pitting and crevice corrosion in chloride solutions 4. **Excellent Fabricability**: Good welding characteristics with minimal susceptibility to post-weld heat treatment cracking 5. **High-Temperature Stability**: Maintains corrosion resistance and mechanical properties at elevated temperatures 6. **Low Carbon Content**: Minimizes sensitization and ensures excellent performance in as-welded conditions 7. **Proven Reliability**: Extensive service history in the most aggressive industrial environments 8. **Pitting Resistance Equivalent (PRE ~69)**: Outstanding resistance to localized corrosion --- **Conclusion** HP Alloys Alloy C-276 represents a premier corrosion-resistant nickel-based superalloy that delivers unparalleled performance in the most severe industrial environments. Its sophisticated chemical composition, featuring optimized levels of chromium, molybdenum, and tungsten, provides exceptional resistance to a broad spectrum of corrosive media encountered in chemical processing, pollution control, and other demanding industries. The alloy's excellent combination of mechanical properties, fabricability, and proven corrosion performance makes it the material of choice for critical applications where equipment reliability and long service life are essential. Supported by comprehensive international standards and rigorous quality certifications, Alloy C-276 continues to set the benchmark for reliability and performance in extreme operating conditions, providing engineers and designers with a trusted solution for the world's most challenging corrosion problems.

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 3432 gallon liquid totes Special package is available on request.