Haynes 242 alloy，1

### **Haynes 242® Alloy - Nickel-Molybdenum-Chromium Alloy with Unique Properties** #### **Overview** **Haynes 242® Alloy** is a nickel-molybdenum-chromium alloy specifically engineered to exhibit an exceptional combination of low thermal expansion characteristics, high strength, and excellent corrosion resistance. This age-hardenable alloy develops its unique properties through the formation of an ordered orthorhombic phase (Ni₂(Mo,Cr)) during aging, making it particularly valuable for applications requiring dimensional stability across wide temperature ranges. --- #### **Chemical Composition (Weight %)** | Element | Content (%) | Function | |---------|-------------|-----------| | **Nickel (Ni)** | **Balance** | **Base matrix providing corrosion resistance** | | **Molybdenum (Mo)** | **24.0-26.0** | **Primary strengthening element, forms ordered phases** | | **Chromium (Cr)** | **7.0-9.0** | **Enhances oxidation resistance and stability** | | **Iron (Fe)** | **≤ 2.0** | **Controlled impurity** | | **Cobalt (Co)** | **≤ 0.50** | **Controlled impurity** | | **Manganese (Mn)** | **≤ 0.80** | **Deoxidizer and sulfur control** | | **Silicon (Si)** | **≤ 0.80** | **Controlled impurity** | | **Aluminum (Al)** | **≤ 0.50** | **Controlled impurity** | | **Carbon (C)** | **≤ 0.03** | **Minimized for optimal properties** | | **Boron (B)** | **≤ 0.006** | **Grain boundary strengthening** | --- #### **Physical Properties** | Property | Value / Description | |----------|---------------------| | **Density** | **9.08 g/cm³ (0.328 lb/in³)** | | **Melting Range** | **1315-1370°C (2400-2500°F)** | | **Electrical Resistivity** | **1.38 μΩ·m** | | **Thermal Conductivity** | **10.5 W/m·K (at 21°C)** | | **Coefficient of Thermal Expansion** | **9.8 μm/m·°C (21-427°C)** | | **Specific Heat Capacity** | **420 J/kg·K** | | **Magnetic Permeability** | **< 1.005 (essentially non-magnetic)** | --- #### **Mechanical Properties (Aged Condition)** | Property | Room Temperature | 540°C (1000°F) | 650°C (1200°F) | |----------|------------------|-----------------|-----------------| | **Tensile Strength** | **1100 MPa (160 ksi)** | **965 MPa (140 ksi)** | **825 MPa (120 ksi)** | | **Yield Strength (0.2% Offset)** | **655 MPa (95 ksi)** | **620 MPa (90 ksi)** | **585 MPa (85 ksi)** | | **Elongation** | **25%** | **20%** | **18%** | | **Young's Modulus** | **224 GPa (32.5 × 10⁶ psi)** | **195 GPa (28.3 × 10⁶ psi)** | **175 GPa (25.4 × 10⁶ psi)** | --- #### **Key Characteristics & Applications** **Key Characteristics:** - **Low Thermal Expansion**: Similar to ferritic steels, enabling compatibility in composite structures - **High Strength-to-Stiffness Ratio**: Excellent mechanical properties at elevated temperatures - **Age-Hardenable**: Develops strength through precipitation of ordered orthorhombic phase - **Good Oxidation Resistance**: Suitable for service up to 815°C (1500°F) - **Excellent Fatigue Resistance**: Superior performance under cyclic loading conditions - **Non-Magnetic**: Essential for applications requiring magnetic transparency **Typical Applications:** - **Aerospace Components**: Seals, rings, and casings for gas turbine engines - **Power Generation**: Gas turbine components and high-temperature fasteners - **Chemical Processing**: Equipment requiring thermal stability and corrosion resistance - **Precision Instruments**: Components demanding dimensional stability - **Medical Devices**: Implantable devices and surgical instruments - **Electronic Packaging**: Where thermal management is critical - **Oil & Gas**: Downhole tools and completion equipment --- #### **Heat Treatment Response** | Treatment | Temperature | Time | Resulting Condition | |-----------|-------------|------|---------------------| | **Solution Annealing** | **1120-1170°C (2050-2140°F)** | **Rapid Cool** | **Soft, workable condition** | | **Aging Treatment** | **650°C (1200°F)** | **16 hours** | **Peak strength condition** | | **Stress Relieving** | **870°C (1600°F)** | **1 hour** | **Stress-free condition** | --- #### **International Standards & Specifications** | Standard | Designation | Description | |----------|-------------|-------------| | **ASTM** | **B435** | **Plate, Sheet, and Strip** | | **ASTM** | **B564** | **Forgings** | | **ASTM** | **B619** | **Welded Pipe and Tube** | | **AMS** | **5873** | **Sheet, Strip, and Plate** | | **UNS** | **N10242** | **Unified Numbering System** | | **ASME** | **Code Case** | **Pressure vessel applications** | --- #### **Fabrication & Processing** **Available Forms:** - **Sheet and Plate**: 0.5 mm to 50 mm thickness - **Bar and Rod**: 5 mm to 200 mm diameter - **Pipe and Tube**: Various diameters and wall thicknesses - **Wire**: For specialized applications - **Forgings**: Custom components **Processing Considerations:** - **Machining**: Best performed in annealed condition before aging - **Welding**: Compatible with GTAW and GMAW using matching filler metal - **Forming**: Good cold formability in solution-annealed condition - **Aging Response**: Critical to achieve optimal properties --- #### **Corrosion Resistance** | Environment | Performance | Temperature Limit | |-------------|-------------|-------------------| | **Oxidizing Atmospheres** | **Good** | **815°C (1500°F)** | | **Reducing Atmospheres** | **Excellent** | **Varies by specific environment** | | **Chloride Solutions** | **Very Good** | **Room to elevated temperatures** | | **Acidic Environments** | **Good** | **Concentration and temperature dependent** | --- #### **Comparison with Competitive Alloys** | Property | Haynes 242 | Inconel 718 | Waspaloy | Incoloy 909 | |----------|------------|-------------|----------|-------------| | **Thermal Expansion** | **Low** | Medium | Medium | **Low** | | **Max Service Temperature** | **815°C** | 650°C | 815°C | 650°C | | **Strength at 650°C** | **Excellent** | Good | Very Good | Good | | **Fabricability** | **Good** | Excellent | Good | Good | --- #### **Summary** **Haynes 242® Alloy** represents a unique class of nickel-based superalloy that combines low thermal expansion characteristics with high strength and excellent corrosion resistance. Its ability to maintain dimensional stability while providing robust mechanical performance at elevated temperatures makes it particularly valuable for aerospace, power generation, and precision engineering applications. The alloy's age-hardenable nature allows for tailoring of mechanical properties to specific application requirements, while its comprehensive standardization ensures consistent quality and reliable performance. Haynes 242 continues to be specified for demanding applications where conventional high-temperature alloys cannot provide the necessary combination of thermal stability, mechanical strength, and corrosion resistance.

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 3242 gallon liquid totes Special package is available on request.