Ni-SA 625 Nickel Super Alloy,Ni-SA (Nickel Super Alloys)，1

### **Technical Datasheet: Ni-SA 625 Nickel Super Alloy** **Classification:** Nickel-Chromium-Molybdenum-Niobium Superalloy **Common Names:** Ni-SA 625, Alloy 625, UNS N06625 **Alternative Designations:** INCONEL® 625, Hastelloy® C-625 --- #### **1.0 Introduction** **Ni-SA 625** is a nickel-chromium-molybdenum superalloy renowned for its exceptional combination of **high strength, excellent fabricability, and outstanding corrosion resistance**. The "Ni-SA" designation signifies its classification within the family of Nickel Super Alloys. Its superior properties are derived from the solid-solution strengthening effect of molybdenum and niobium in a nickel-chromium matrix. A key advantage of Alloy 625 is that it retains significant strength and oxidation resistance from cryogenic temperatures up to 1800°F (1000°C), and it exhibits excellent resistance to a wide range of corrosive environments, including pitting, crevice corrosion, and stress-corrosion cracking. --- #### **2.0 Chemical Composition (Weight %)** The chemical composition is the foundation of the alloy's performance and is tightly controlled by international standards. | Element | Minimum | Maximum | Key Function | | :--- | :--- | :--- | :--- | | **Nickel (Ni)** | **Balance** | | Forms the stable, corrosion-resistant austenitic matrix. | | **Chromium (Cr)** | 20.0 | 23.0 | Provides resistance to oxidizing media and high-temperature oxidation. | | **Molybdenum (Mo)** | 8.0 | 10.0 | Imparts resistance to reducing media and provides solid-solution strengthening. | | **Niobium (Nb)** | 3.15 | 4.15 | Acts as a potent solid-solution strengthener; forms stable carbides. | | **Iron (Fe)** | - | 5.0 | Incidental element; kept low for optimal corrosion resistance. | | **Aluminum (Al)** | - | 0.40 | - | | **Titanium (Ti)** | - | 0.40 | - | | **Carbon (C)** | - | 0.10 | - | | **Manganese (Mn)** | - | 0.50 | - | | **Silicon (Si)** | - | 0.50 | - | | **Phosphorus (P)** | - | 0.015 | - | | **Sulfur (S)** | - | 0.015 | - | --- #### **3.0 Physical Properties** | Property | Value | Condition | | :--- | :--- | :--- | | **Density** | 8.44 g/cm³ (0.305 lb/in³) | At room temperature | | **Melting Range** | 1290 - 1350 °C (2350 - 2460 °F) | - | | **Thermal Expansion Coefficient** | 12.8 μm/m·°C | 20 - 100°C | | **Thermal Conductivity** | 9.8 W/m·K | At 100°C | | **Electrical Resistivity** | 129 μΩ·cm | At room temperature | | **Modulus of Elasticity** | 207 GPa (30.0 x 10⁶ psi) | At room temperature | --- #### **4.0 Mechanical Properties (Typical for Annealed Condition)** | Property | Value at Room Temperature | | :--- | :--- | | **Tensile Strength** | ≥ 827 MPa (120 ksi) | | **Yield Strength (0.2% Offset)** | ≥ 414 MPa (60 ksi) | | **Elongation** | ≥ 30% | --- #### **5.0 Key Characteristics & Applications** **5.1 Key Characteristics:** * **Excellent Corrosion Resistance:** Superior performance in a wide range of acids, chlorides, and saline solutions. Highly resistant to pitting and crevice corrosion. * **High-Temperature Strength:** Maintains excellent tensile, creep, and rupture strength up to 1000°C due to solid-solution strengthening. * **Oxidation Resistance:** Forms a protective, adherent chromia oxide scale, providing excellent resistance to air oxidation at high temperatures. * **Excellent Fabricability and Weldability:** Can be readily formed and welded using common techniques without post-weld heat treatment to maintain corrosion resistance. **5.2 Primary Applications:** * **Aerospace & Defense:** Combustion liners, engine ducting, exhaust systems, and thrust reversers. * **Marine Engineering:** Propeller blades, submarine components, seawater heat exchangers, and piping systems. * **Chemical Processing:** Reactors, heat exchangers, and piping for aggressive chemical environments. * **Oil & Gas:** Downhole and subsea equipment, umbilicals, and control line tubing. * **Pollution Control:** Flue gas desulfurization (FGD) system components like scrubbers and stack liners. --- #### **6.0 International Standards** Ni-SA 625 / Alloy 625 is covered by a comprehensive set of international standards for various product forms. | Product Form | Standard Number | Governing Body | | :--- | :--- | :--- | | **Plate, Sheet, Strip** | ASTM B443 / ASME SB-443 | ASTM International / ASME | | **Plate, Sheet, Strip** | AMS 5599 | SAE International (Aerospace) | | **Bar, Forgings, Ring** | ASTM B446 / ASME SB-446 | ASTM International / ASME | | **Bar, Forgings, Ring** | AMS 5666 | SAE International (Aerospace) | | **Seamless Pipe & Tube** | ASTM B444 / ASME SB-444 | ASTM International / ASME | | **Welded Tube** | ASTM B704 / ASME SB-704 | ASTM International / ASME | | **Welding Wire** | AWS A5.14 / AMS 5837 | AWS / SAE International | | **Welding Electrodes** | AWS A5.11 | AWS | | **European Standard** | DIN 2.4856 | Deutsches Institut für Normung | **Note:** "INCONEL" is a registered trademark of Special Metals Corporation. "Hastelloy" is a registered trademark of Haynes International. "Ni-SA 625" is used here as a generic technical designation for this alloy family. Specifications should always be confirmed with the material supplier.

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 3271 gallon liquid totes Special package is available on request.