Ni-SA 718 Nickel Super Alloy,Ni-SA (Nickel Super Alloys)，1

### **Technical Datasheet: Ni-SA 718 (INCONEL® 718) Nickel-Based Superalloy** **Classification:** Precipitation-Hardenable Nickel-Chromium Superalloy **UNS Designation:** N07718 **Common Names:** Ni-SA 718, INCONEL® 718, Alloy 718 --- #### **1.0 Introduction** **Ni-SA 718** is a premier precipitation-hardenable nickel-chromium superalloy containing significant amounts of iron, niobium, and molybdenum. As part of the Ni-SA (Nickel Super Alloys) family, it strengthens through the precipitation of coherent body-centered tetragonal gamma double prime (γ'') phase [Ni₃Nb] in its austenitic matrix. The alloy's exceptional combination of **high strength, excellent fatigue resistance, and outstanding creep-rupture properties** up to 1300°F (700°C), coupled with **superior weldability** and resistance to post-weld strain-age cracking, makes it one of the most widely used superalloys in aerospace and high-temperature applications. --- #### **2.0 Chemical Composition (Weight %)** | Element | Minimum | Maximum | Key Function | |---------|---------|---------|--------------| | **Nickel (Ni)** | **Balance** | | Austenitic matrix former | | **Chromium (Cr)** | 17.0 | 21.0 | Oxidation and corrosion resistance | | **Iron (Fe)** | **Balance** | | Low-cost matrix element (typically ~18%) | | **Niobium (Nb)** | 4.75 | 5.50 | **Primary strengthener** - forms γ'' phase (Ni₃Nb) | | **Molybdenum (Mo)** | 2.80 | 3.30 | Solid-solution strengthening | | **Titanium (Ti)** | 0.65 | 1.15 | Forms gamma prime (γ') phase | | **Aluminum (Al)** | 0.20 | 0.80 | Forms gamma prime (γ') phase | | **Cobalt (Co)** | - | 1.00 | Controlled impurity | | **Carbon (C)** | - | 0.08 | Carbide formation | | **Manganese (Mn)** | - | 0.35 | - | | **Silicon (Si)** | - | 0.35 | - | | **Boron (B)** | - | 0.006 | Grain boundary strengthening | --- #### **3.0 Physical Properties** | Property | Value | Condition | |----------|-------|-----------| | **Density** | 8.19 g/cm³ (0.296 lb/in³) | Room temperature | | **Melting Range** | 1260-1336°C (2300-2440°F) | - | | **Thermal Expansion** | 13.0 μm/m·°C | 20-100°C | | **Thermal Conductivity** | 11.4 W/m·K | 100°C | | **Electrical Resistivity** | 125 μΩ·cm | Room temperature | | **Modulus of Elasticity** | 205 GPa (29.8×10⁶ psi) | Room temperature | --- #### **4.0 Mechanical Properties (Typical for Aged Condition)** | Property | Room Temperature | 1200°F (650°C) | |----------|------------------|----------------| | **Tensile Strength** | 1310 MPa (190 ksi) | 1035 MPa (150 ksi) | | **Yield Strength (0.2% Offset)** | 1035 MPa (150 ksi) | 895 MPa (130 ksi) | | **Elongation** | 12% | 12% | --- #### **5.0 Key Characteristics & Applications** **5.1 Key Characteristics:** - **Excellent Weldability**: Superior resistance to strain-age cracking - **High Strength Retention**: Maintains properties from cryogenic to 700°C - **Good Oxidation Resistance**: Suitable for high-temperature service - **Outstanding Fatigue Strength**: Excellent resistance to cyclic loading **5.2 Primary Applications:** - **Aerospace**: Turbine blades, disks, rings, shafts, and casings - **Gas Turbines**: Compressor and turbine components - **Nuclear Reactors**: Core components and fasteners - **Oil & Gas**: Downhole tools, wellhead components - **Rocket Motors**: Cryogenic components and engine parts --- #### **6.0 International Standards** | Product Form | Standard Number | Governing Body | |--------------|----------------|----------------| | **Bar & Forgings** | AMS 5662 | SAE International | | **Sheet & Strip** | AMS 5596 | SAE International | | **Welding Wire** | AMS 5832 | SAE International | | **Plate** | ASTM B670 | ASTM International | | **Bar & Billet** | ASTM B637 | ASTM International | | **Welding Electrodes** | AWS A5.11/ENiCrFe-2 | AWS | **Note:** "INCONEL" is a registered trademark of Special Metals Corporation. "Ni-SA 718" is used as a generic technical designation. The alloy requires specific solution and aging heat treatments (typically 1700-1850°F solution + 1325°F aging) to achieve optimal properties.

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 3273 gallon liquid totes Special package is available on request.