Alloy 75,Haynes 75,UNS N06075,E FORU

### **Alloy 75 / Haynes® 75 / UNS N06075** **Nickel-Chromium Solid-Solution Strengthened Alloy for High-Temperature Service** #### **1. Overview** Alloy 75, commercially known as **Haynes® 75**, is a nickel-chromium austenitic alloy that derives its strength from solid-solution hardening. Developed for high-temperature service, this alloy offers excellent oxidation resistance, good elevated temperature strength, and outstanding formability. Unlike precipitation-hardenable superalloys, Haynes 75 is used in the solution-annealed condition, making it readily fabricable and weldable. It serves as a cost-effective solution for various high-temperature components across multiple industries. #### **2. Chemical Composition (Weight %)** The typical chemical composition of Haynes 75 is outlined below. The balance is Nickel (Ni). | Element | Content (%) | Key Function | | :--- | :--- | :--- | | **Nickel (Ni)** | Balance | Forms the stable austenitic matrix, providing fundamental high-temperature strength and corrosion resistance. | | **Chromium (Cr)** | 18.0 - 21.0 | Confers outstanding resistance to oxidation and scaling at high temperatures. | | **Iron (Fe)** | 3.0 - 6.0 | Balances cost; controlled to maintain microstructural stability. | | **Titanium (Ti)** | 2.0 - 2.75 | Strengthens the alloy through solid-solution hardening and forms stable carbides. | | **Cobalt (Co)** | 3.0 - 6.0 | Enhances solid-solution strengthening and high-temperature stability. | | **Manganese (Mn)** | 1.0 max | Improves hot workability and acts as a deoxidizer. | | **Silicon (Si)** | 1.0 max | Enhances oxidation resistance at elevated temperatures. | | **Aluminum (Al)** | 0.5 - 1.0 | Contributes to oxidation resistance and forms strengthening phases. | | **Carbon (C)** | 0.05 - 0.15 | Enhances high-temperature strength through carbide formation. | | **Boron (B)** | 0.005 - 0.025 | Improves creep strength and grain boundary stability. | | **Zirconium (Zr)** | 0.02 - 0.12 | Enhances creep-rupture properties and thermal stability. | | **Sulfur (S)** | 0.015 max | Impurity, kept low to prevent hot shortness. | #### **3. Physical Properties** | Property | Value / Condition | | :--- | :--- | | **Density** | 8.23 g/cm³ (0.297 lb/in³) | | **Melting Range** | ~ 1290 - 1380 °C (2350 - 2516 °F) | | **Mean Coefficient of Thermal Expansion** | 20 - 540°C (68 - 1004°F): **14.2 x 10⁻⁶/°C** (7.9 x 10⁻⁶/°F)
20 - 980°C (68 - 1796°F): **16.1 x 10⁻⁶/°C** (8.9 x 10⁻⁶/°F) | | **Thermal Conductivity** | 17.5 W/m·K (121 Btu·in/hr·ft²·°F) at 21°C (70°F) | | **Specific Heat** | 455 J/kg·K (0.109 Btu/lb·°F) at 21°C (70°F) | | **Electrical Resistivity** | 1.15 μΩ·m at 21°C (70°F) | | **Modulus of Elasticity (Young's Modulus)** | 221 GPa (32.0 x 10⁶ psi) at 21°C (70°F) | | **Magnetic Permeability** | Essentially non-magnetic in annealed condition. | #### **4. Mechanical Properties (Typical for Annealed Condition)** | Property | At Room Temperature | At 815°C (1500°F) | | :--- | :--- | :--- | | **Tensile Strength** | 785 - 965 MPa (114 - 140 ksi) | ~145 MPa (21 ksi) | | **Yield Strength (0.2% Offset)** | 345 - 620 MPa (50 - 90 ksi) | ~110 MPa (16 ksi) | | **Elongation (in 50 mm / 2 in)** | 25% - 45% | ~40% | | **Hardness (Rockwell B)** | 85 - 100 HRB | - | #### **5. International Standards** Haynes 75 is covered by several international and industry-specific standards: * **ASTM:** * **B 166:** Standard Specification for Nickel-Chromium-Iron Alloy Rod, Bar, and Wire * **B 168:** Standard Specification for Nickel-Chromium-Iron Alloy Plate, Sheet, and Strip * **AMS:** AMS 5548 (Sheet, Strip, and Plate) * **ASME:** SB-166, SB-168 (Approved for use in ASME Boiler and Pressure Vessel Code) * **UNS:** N06075 * **EN (European Standard):** 2.4951 (Material Number) * **DIN:** DIN 17742, DIN 17752 (Werkstoff Nr. 2.4951) #### **6. Product Applications** Haynes 75 is widely used in applications demanding reliability at high temperatures: * **Aerospace & Gas Turbines:** * Combustion chamber components * Afterburner parts * Turbine seals and shrouds * **Industrial Furnaces & Heat Treatment:** * Heat treatment fixtures and baskets * Radiant tubes * Thermocouple protection sheaths * **Power Generation:** * Boiler components * Heat exchanger parts * **Chemical Processing:** * High-temperature reactor components * Furnace parts in chemical plants #### **7. Key Characteristics & Advantages** * **Excellent Oxidation Resistance:** Superior scaling resistance up to 1175°C (2150°F) due to its optimized chromium content. * **Good High-Temperature Strength:** Maintains useful mechanical properties at elevated temperatures through solid-solution strengthening. * **Outstanding Fabricability:** Excellent formability and weldability using conventional methods. * **Thermal Stability:** Resists microstructural degradation during long-term exposure at high temperatures. * **Cost-Effective Performance:** Provides an excellent balance between performance and cost for high-temperature applications. * **Creep Resistance:** Good resistance to creep deformation at elevated temperatures. --- **Disclaimer:** *Haynes® 75 is a registered trademark of Haynes International, Inc. The values provided are typical and for informational purposes only. For critical applications, always consult the official material data sheets from the supplier and relevant design codes.*

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 1655 gallon liquid totes Special package is available on request.