What is the difference between Alloy 925 and 718?
Both 925 alloy (Incoloy 925) and 718 alloy (Inconel 718) are precipitation-hardening nickel alloys, but due to its higher copper/molybdenum content, 925 alloy exhibits superior resistance to sulfide stress cracking (SSC) and corrosion in acidic environments, making it ideal for the oil and gas industry. In contrast, 718 alloy has a higher nickel content, providing excellent strength at high temperatures, making it suitable for aerospace and general high-temperature applications. However, under specific corrosive conditions, 925 alloy can achieve comparable strength to 718 alloy while offering better corrosion resistance.
What are the applications of Alloy 718?
Alloy 718 has become the most widely used superalloy in the aerospace industry. It is the most frequently used alloy by General Electric Aircraft Engines (GEAE), and is used in critical rotating components, airfoil components, support structures, and pressure vessels.
Inconel 718 Alloy
Inconel 718 is a precipitation-hardening nickel-chromium alloy that combines corrosion resistance, high strength, and good machinability. It exhibits excellent fatigue strength, age-hardening response, and good weldability. The alloy contains significant amounts of niobium, molybdenum, titanium, aluminum, and cobalt, which contribute to its unique properties. This composition makes it an ideal material for jet engine components such as blades, discs, shafts, hubs, and casings. Furthermore, due to its excellent low-temperature toughness, Inconel 718 is also commonly used in cryogenic applications.
Inconel 925 Alloy
Inconel 925 is also a precipitation-hardening nickel-chromium alloy, but unlike 718, it contains a higher molybdenum content (2%-4%). Because the added molybdenum gives the alloy better creep strength at high temperatures, Inconel 925 is primarily used in high-temperature applications, such as turbine blades or exhaust systems in jet engines. Additionally, the increased molybdenum content improves its resistance to chloride stress corrosion cracking (SCC), making it suitable for use in chemical processing equipment where hydrochloric acid is present.
Inconel 718 and Inconel 925 Chemical Composition
| Alloy 925 (Incoloy 925) | Alloy 718 (Inconel 718) | |
|---|---|---|
| 42-46% | 50-55% | |
| 19.5-23.5% | 17-21% | |
| 2.5-3.5% | 2.8-3.3% | |
| 1.5-3.0% | - | |
| 1.9-2.4% | 0.65-1.15% | |
| 0.1-0.5% | 0.2-0.8% | |
| - | 4.75-5.5% |
Inconel 718 and Inconel 925 Mechanical Properties
| Alloy 925 | Alloy 718 | |
|---|---|---|
| ≥1034 MPa (150 ksi) | 1034-1241 MPa (150-180 ksi) | |
| ≥1276 MPa (185 ksi) | 1241-1480 MPa (180-215 ksi) | |
| Rockwell C30-40 | Rockwell C35-45 | |
| Excellent (up to 700°C) |
Inconel 718 and Inconel 925 Corrosion Resistance
| Alloy 925 | Alloy 718 | |
|---|---|---|
Inconel 718 and Inconel 925 Applications
| Alloy 925 | Alloy 718 | |
|---|---|---|
| ✗ | ||
| ✓ (seawater-resistant components) | ✗ | |
| ✓ | ✗ | |
| ✗ | ||
| ✗ | ✓ | |
| High-Temperature Fasteners & Springs | ✗ | ✓ |
Why Choose Gnee as Your Nickel-Based Alloy Supplier
✅ Over 18 years of export experience, products sold to more than 80 countries
✅ Fast delivery within 7-15 days, supported by global logistics partners
Moisture-proof packaging
Gnee Steel is a professional manufacturer of nickel-based alloys, including Nickel 201, Nickel 202, Hastelloy C-276, Hastelloy C-22, Hastelloy B, Hastelloy C-4, Inconel 600, Inconel 625, Inconel 718, Inconel X-750, Incoloy 800, Incoloy 800H/HT, Incoloy 825, Monel 400, Monel K500, and other high-temperature alloy materials. We specialize in the production and sales of alloy materials. Gnee Steel's products are widely used in aerospace, chemical, power generation, automotive, nuclear energy, and other fields, and we can provide customized alloy material solutions according to customer needs. For inquiries about alloy material prices or customized alloy material solutions, please feel free to contact us via email at ss@gneemetal.com for a quote.
