What are the differences between Inconel 718 and 725 alloys?
What are the differences between Inconel 718 and 725 alloys?
Compared to Inconel 718, Inconel 725 has a significantly higher molybdenum content, resulting in superior corrosion resistance and high-temperature strength. Inconel 718 is a more versatile general-purpose alloy suitable for a wide range of applications, while Inconel 725 is specifically designed for extreme corrosive or high-temperature environments where Inconel 718 cannot perform.
What is the difference between Inconel 718 and 750?
Compared to Inconel X-750, Inconel 718 contains more chromium. This makes Inconel 718's oxidation resistance superior to Inconel X-750. Furthermore, Alloy 718 contains molybdenum, while Alloy X-750 does not. The addition of molybdenum improves Inconel 718's resistance to reducing corrosion.
Inconel 718
Composition: Inconel 718 typically contains approximately 50-55% nickel, along with significant amounts of chromium (approximately 17-21%), iron (approximately 18.5%), and niobium (approximately 5%), and trace amounts of molybdenum, titanium, aluminum, and tantalum.
Properties:
Strength: Excellent strength, especially at high temperatures (up to approximately 704°C or 1300°F).
Corrosion Resistance: Good oxidation and corrosion resistance.
Applications: Widely used in aerospace, gas turbines, nuclear reactors, and other high-temperature applications requiring extremely high strength and corrosion resistance. It is renowned for its reliability and high-temperature performance retention under high-stress environments.
Inconel 725
Composition: Inconel 725 is a nickel-chromium alloy with added niobium, titanium, and molybdenum. Its typical composition is approximately 58% nickel, a significant amount of chromium (approximately 19%), niobium (approximately 5.5%), titanium (approximately 1.75%), and small amounts of molybdenum (approximately 3%) and aluminum (approximately 0.4%).
Properties:
Strength: Higher than Inconel 718, especially in the temperature range of 1200–1800°F (649–982°C).
Corrosion Resistance: Good corrosion resistance and oxidation resistance, similar to Inconel 718.
Applications: Primarily used in high-pressure environments requiring high strength at high temperatures, such as jet engine components, high-strength fasteners, and nuclear reactors.
| Feature | Inconel 718 | Inconel 725 |
|---|---|---|
| Primary Use | General-purpose high-strength applications | Demanding environments requiring high strength and corrosion resistance |
| Molybdenum Content | Lower | Higher (7-9%) |
| Corrosion Resistance | Good, but lower than 725 | Superior, especially in aggressive environments |
| Strength at High Temperatures | Good | Superior, especially at temperatures above what 718 can reliably handle |
| Key Alloying Elements | Nickel, Chromium, Niobium, Molybdenum, Iron | Nickel, Chromium, Niobium, Molybdenum, Titanium |
| Pitting Resistance Equivalent Number (PREN) | Exceeds 31 | Exceeds 45 |
| Common Applications | Gas turbines, aircraft components, general high-temperature use | Aerospace, high-performance engineering, sour oil and gas wells |
Why Choose Gnee as Your Nickel-Based Alloy Supplier
✅ Over 18 years of export experience, products sold to more than 80 countries
✅ Certified by ISO, SGS, and BV
✅ Global inventory of Inconel, Hastelloy, Incoloy, and Monel alloy tubing, plates, and bars
✅ Custom processing services available – including cutting, polishing, CNC machining, and packaging
✅ Fast delivery within 7-15 days, supported by global logistics partners
📦 Packaging and Shipping
All stainless steel products are packaged using the following methods:
Wooden pallets or crates
Moisture-proof packaging
Labels with furnace number, standard, and size labels
Shipped worldwide by sea, air, or express
Gnee Steel is a supplier of Inconel 718 alloy, offering a wide range of products including: seamless pipe (sizes: 4-219 mm; thickness: 0.5-20 mm); welded pipe (sizes: 5.0-1219.2 mm; thickness: 0.5-20 mm); plates (thickness: 0.1 to 100 mm; width: 10-2500 mm); strips; alloy round bars (diameter: 3-800 mm); flat bars (thickness: 2-100 mm; width: 10-500 mm); hexagonal bars (size: 2-100 mm); wire rods; and extruded profiles. We collaborate with steel mills to provide our customers with Inconel 718 alloy products that meet or exceed numerous leading industry standards, including ASTM, ASME, SAE, AMS, ISO, DIN, EN, and BS standards.
Gnee Steel stocks and sells Inconel 718, pipes, plates, strips, round bars, flat bars, forged billets, hexagonal steel, wire rods, and extruded profiles. Please feel free to contact us at ss@gneesteel.com for a quote.
