Alloy 706，Inconel 706 Fittings，UNS N09706，EFORU

British Specs:，American Specs:AMS 5701 Bar and Forgings AMS 5702 Bar and Forgings AMS 5703 Bar and Forgings AMS 5605 Sheet, Strip and Plate AMS 5606 Sheet, Strip and Plate，German Specs:

### **Product Introduction: Alloy 706 / Inconel 706 Fittings (UNS N09706)** #### **Overview** Alloy 706, commonly known by its trade name Inconel® 706, is a precipitation-hardenable nickel-iron-chromium superalloy. It is renowned for its exceptional combination of high strength, good fabricability, and excellent resistance to oxidation and corrosion. Inconel 706 fittings are critical components designed for use in demanding environments where reliability and performance under stress and high temperatures are paramount. A key characteristic of Alloy 706 is its lower thermal expansion coefficient compared to similar alloys like Alloy 718, making it particularly advantageous for applications requiring dimensional stability over a wide temperature range. --- #### **Chemical Composition** The typical chemical composition of Alloy 706 (UNS N09706) is outlined in the table below: | Element | Content (%) | | :--- | :--- | | **Nickel (Ni)** | 39.0 - 44.0 | | **Chromium (Cr)** | 14.5 - 17.5 | | **Iron (Fe)** | Balance | | **Niobium (Nb)** | 2.5 - 3.3 | | **Titanium (Ti)** | 1.5 - 2.0 | | **Molybdenum (Mo)** | ≤ 0.30 | | **Aluminum (Al)** | 0.20 - 0.40 | | **Carbon (C)** | ≤ 0.08 | | **Manganese (Mn)** | ≤ 0.35 | | **Silicon (Si)** | ≤ 0.35 | | **Sulfur (S)** | ≤ 0.015 | | **Copper (Cu)** | ≤ 0.30 | | **Boron (B)** | 0.003 - 0.01 | *The primary strengthening mechanism is achieved through the precipitation of gamma prime [γ' Ni₃(Al, Ti)] and gamma double prime [γ'' Ni₃Nb] phases during heat treatment.* --- #### **Physical Properties** The physical properties of Alloy 706 are critical for design and application engineering. | Property | Metric Value | Imperial Value | | :--- | :--- | :--- | | **Density** | 8.05 g/cm³ | 0.291 lb/in³ | | **Melting Range** | 1370 - 1430 °C | 2500 - 2600 °F | | **Specific Heat (20°C)** | 450 J/kg·K | 0.108 Btu/lb·°F | | **Thermal Conductivity (20°C)** | 12.5 W/m·K | 86.7 Btu·in/hr·ft²·°F | | **Thermal Expansion Coefficient (20-100°C)** | 12.8 μm/m·°C | 7.1 μin/in·°F | | **Electrical Resistivity** | 1.18 μΩ·m | - | | **Modulus of Elasticity (Tensile)** | 204 GPa | 29.5 x 10⁶ psi | --- #### **Mechanical Properties (Typical for Fittings after Heat Treatment)** Mechanical properties are highly dependent on the heat treatment condition. The standard heat treatment for optimum strength is Solution Annealed + Aged. **Condition: Solution Annealed + Aged (SA + Aged)** * **Ultimate Tensile Strength:** ≥ 1240 MPa (180 ksi) * **Yield Strength (0.2% Offset):** ≥ 1030 MPa (150 ksi) * **Elongation:** ≥ 12% * **Hardness:** ≥ 36 HRC --- #### **International Standards** Inconel 706 fittings are manufactured to meet various international standards for material and dimensions. * **Material Standards:** * **ASTM B805:** Standard Specification for Precipitation Hardening Nickel Alloy Bars, Forgings, and Forging Stock for High-Temperature Service. * **AMS 7857:** Aerospace Material Specification for Bars, Forgings, and Rings. * **ISO 9724:** Nickel and nickel alloys — Forgings (may be applicable). * **Dimensional Standards (for Fittings):** * **ASME B16.11:** Forged Fittings, Socket-Welding and Threaded. * **MSS SP-79:** Socket-Welding Reducer Inserts. * **Customer-specific drawings** for custom or non-standard fittings. --- #### **Product Applications** Inconel 706 fittings are utilized in severe service applications across several high-tech industries: * **Aerospace & Gas Turbines:** A primary application is in the hot sections of jet engines and land-based gas turbines. Fittings are used in fuel and hydraulic systems, as well as structural components that require high strength-to-weight ratios at elevated temperatures. * **Oil & Gas (Downhole):** Ideal for high-strength components in deep well drilling, such as hanger systems, subs, and mandrels, where resistance to sour gas (H₂S) and high pressure is critical. * **Power Generation:** Used in advanced steam turbines, nuclear reactors, and other high-temperature power generation systems. * **Chemical Processing:** Employed in fittings for equipment handling corrosive chemicals at elevated temperatures and pressures. --- #### **Key Advantages** * **High Strength:** Offers impressive tensile and yield strength, especially after aging, comparable to Alloy 718 but with better machinability. * **Excellent Fabricability:** Demonstrates good forgeability and machinability in the solution-annealed condition compared to other high-strength superalloys. * **Good Weldability:** Can be welded using common techniques, though post-weld heat treatment is typically required to restore properties. * **Low Thermal Expansion:** Provides superior dimensional stability in thermally cyclic environments. * **Outstanding Creep Resistance:** Maintains its mechanical integrity under constant stress at high temperatures. **Note:** Inconel® is a registered trademark of Special Metals Corporation, a PCC company. Always consult with a qualified materials engineer and refer to the relevant material datasheets for final design and specification. ---

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 1775 gallon liquid totes Special package is available on request.