Haynes 75 Nickel Alloy,Haynes alloy 75，1

### **Introduction to Haynes® 75 (UNS N06075) Nickel Alloy** **Haynes® 75** is a nickel-chromium solid-solution strengthened alloy that has been a trusted material for high-temperature applications since the 1940s. While newer superalloys have been developed, Haynes 75 remains a cost-effective and highly reliable choice for use in oxidizing atmospheres up to 2200°F (1200°C). Its excellent combination of high-temperature strength, outstanding resistance to oxidation, and good fabricability makes it a staple in aerospace and industrial heating industries. Unlike many other nickel-based alloys, Haynes 75 is not hardened by precipitation aging. Its strength is derived from the solid-solution strengthening effect of chromium and the work-hardening it receives during manufacturing. --- ### **Chemical Composition (Weight %, typical)** The composition of Haynes 75 is relatively simple and optimized for oxidation resistance. | Element | Minimum | Maximum | Key Function | | :--- | :--- | :--- | :--- | | **Nickel (Ni)** | **Balance** | | Forms the stable, oxidation-resistant matrix. | | **Chromium (Cr)** | 18.0 | 21.0 | **Primary role:** Forms a tenacious, self-healing Cr₂O₃ (chromia) scale for exceptional oxidation resistance. | | **Iron (Fe)** | - | 5.0 | Incidental element; kept low to maintain performance. | | **Titanium (Ti)** | 2.0 | 3.0 | Forms the strengthening gamma prime (γ') phase Ni₃Ti in aged condition; improves creep strength. | | **Manganese (Mn)** | - | 1.0 | - | | **Silicon (Si)** | - | 1.0 | Enhances oxidation resistance. | | **Carbon (C)** | 0.05 | 0.15 | Provides high-temperature strength via carbide formation. | | **Copper (Cu)** | - | 0.5 | - | | **Sulfur (S)** | - | 0.015 | - | *The balanced Ni-Cr-Ti-C composition is key to its performance profile.* --- ### **Physical Properties (Typical)** * **Density:** 8.21 g/cm³ (0.297 lb/in³) * **Melting Range:** 1355 - 1385 °C (2475 - 2525 °F) * **Thermal Expansion Coefficient:** 13.9 μm/m·°C (20-100°C) * **Thermal Conductivity:** 12.5 W/m·K at 100°C * **Modulus of Elasticity (Young's Modulus):** 214 GPa (31 x 10⁶ psi) at 21°C --- ### **Mechanical Properties (Typical at Room Temperature)** Properties can vary with product form and heat treatment. * **Tensile Strength:** 795 - 965 MPa (115 - 140 ksi) * **Yield Strength (0.2% Offset):** 345 - 620 MPa (50 - 90 ksi) * **Elongation:** 30% - 50% ***High-Temperature Strength:*** Haynes 75 retains useful strength at elevated temperatures, with a 1000-hour rupture strength of approximately 110 MPa (16 ksi) at 815°C (1500°F). --- ### **Key Characteristics and Product Applications** #### **Key Characteristics:** 1. **Excellent Oxidation Resistance:** Its high chromium content allows it to form a highly protective and adherent oxide layer, preventing further degradation at high temperatures. 2. **Good High-Temperature Strength:** It maintains good load-bearing capacity and creep resistance at temperatures where many steels would fail. 3. **Good Fabricability:** It can be formed and welded using standard techniques, though it is often used in the solution-annealed state. 4. **Cost-Effectiveness:** Compared to more complex molybdenum- and cobalt-containing superalloys, Haynes 75 offers a favorable balance of performance and cost for many applications. #### **Primary Applications:** Haynes 75 is a workhorse alloy in high-temperature, oxidizing environments. * **Aerospace & Gas Turbines:** * **Combustion Liners and Flame Holders:** A classic and widespread application. * **Afterburner Components** * **Turbine Igniters** * **Exhaust System Components** * **Industrial Heating:** * **Heat Treatment Furnace Components:** Radiant tubes, muffles, retorts, and baskets. * **Heating Element Sheaths and Support Hardware** * **Nuclear Industry:** * **Heat Exchanger Tubes** --- ### **International Standards** Haynes 75 is covered by long-established specifications, primarily from the aerospace sector. | Product Form | Standard | Designation | Notes | | :--- | :--- | :--- | :--- | | **Sheet, Strip, Plate** | **AMS 5542** | Haynes Alloy 75 | The primary and most common specification for sheet and plate forms. | | **Bar, Wire, Forgings** | *Proprietary / Customer Spec* | - | Often supplied to customer-defined specifications based on the AMS 5542 composition. | | **Welding Consumables** | AWS A5.14 | **ERNiCr-3** | This nickel-chromium filler metal is commonly used for welding Haynes 75 and similar alloys. | | **Welding Consumables** | AWS A5.11 | **ENiCr-3** | Matching composition covered electrodes for SMAW (Stick) welding. | **Note:** "Haynes" and "Haynes 75" are registered trademarks of **Haynes International, Inc.** While it is an older alloy, its proven performance ensures it remains a specified material for many critical applications. For new designs, it is always recommended to consult with the manufacturer to ensure it is the most optimal material choice.

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 3260 gallon liquid totes Special package is available on request.