Inconel 625 and 718 Alloy
What is the difference between Inconel 625 and 718?
Inconel 625 and Inconel 718 are both high-temperature alloys with excellent comprehensive properties. The main difference between them is that the performance of Inconel 625 is more inclined towards corrosion resistance, while the performance of Inconel 718 is more inclined towards high strength.
Will Inconel 625 rust?
Inconel 625 (UNS N06625) is a nickel-chromium-molybdenum alloy that has excellent corrosion resistance in a variety of corrosive media, especially pitting and crevice corrosion. However, in corrosive environments, Inconel 625 will corrode like other metals.
What are the benefits of Inconel 625?
In addition to high tensile strength, INCONEL 625 also has high creep strength, high rupture strength and excellent weldability. These properties make it suitable for aerospace applications, including duct and exhaust systems, turbine shrouds and seals, and thrust reverser systems.
What is INCONEL Alloy 718 used for?
INCONEL Alloy 718 is commonly used in the aerospace industry. Engineers are constantly looking to improve engine reliability and efficiency, not to mention extend their service life. High-temperature alloys, especially Alloy 718, are widely chosen for their balance between cost and performance.
Inconel 625 vs 718 Material Properties
| Properties | Inconel 625 | Inconel 718 |
|---|---|---|
| Melting Range | 2350-2460°F (1290-1350°C) | 2300-2437°F (1260-1336°C) |
| Curie Temperature | -320°F (-196°C) |
-320°F (-196°C) (Annealed) 170°F (-112°C) (Annealed and Aged) |
| Density | 0.305lb/cu (8.44gram/cc) |
0.296 (Annealed) 0.297 (Annealed and Aged) |
| Permeability at 200 | 1.0006 |
1.0013 (Annealed) 1.0011(-112°C) (Annealed and Aged) |
| Specific Heat 70°F at( 21°) | 0.098 (410) | 0.104 (435) |
Nickel 625 vs 718 Chemical Composition
| Element | Inconel 625 | Inconel 718 |
|---|---|---|
| Chromium (Cr) | 22 | 17-21 |
| Iron (Fe) | 4 | Balance |
| Titanium (Ti) | 0.3 | 0.65-1.15 |
| Aluminum (Al) | 0.3 | 0.20-0.80 |
| Carbon (C ) | 0.05 | 0.08 max |
| Phosphorous (P) | 0.01 | 0.015max |
| Boron (B) | - | 0.006 max |
| Nickel (Ni) | 60 | 50-55 |
| Molybdenum (Mo) | 9 | 2.80-3.30 |
| Niobium (Nb) | 3.5 | 4.75-5.50 |
| Manganese (Mn) | 0.3 | 0.35 max |
| Silicon (Si) | 0.25 | 0.35 max |
| Sulfur (S) | 0.003 | 0.015 max |
| Cobalt (Co) | - | 1.00 max |
| Tantalum (Ta) | - | 0.30 max |
Alloy 718 and 625 Application
| Alloy | Application |
|---|---|
| 625 |
Molds Gas-Turbine Engine Aircraft Pumps Nuclear Reactors |
| 718 |
Aerospace Medical Devices Combustion Chambers |
Mechanical Properties of Inco 718 & 625
| Properties | Inconel 625 | Inconel 718 |
|---|---|---|
| Elongation at Break | 33 to 34 % | 12 to 50 % |
| Poisson's Ratio | 0.29 | 0.29 |
| Shear Strength | 530 to 600 MPa (77 to 87x 103psi) | 660 to 950 MPa (96 to 140x 103psi) |
| Yield Strength | 320 to 450 MPa (47 to 65x 103 psi) | 510 to 1330 MPa (74 to 190 x 103 psi) |
| Elastic Modulus | 190 GPa (28 x 106 psi) | 200 GPa (30 x 106 psi) |
| Fatigue Strength | 240 to 320 MPa (34 to 47 x 103 psi) | 460 to 760 MPa (67 to 110 x 103 psi) |
| Shear Modulus | 530 to 600 MPa (77 to 87 x 103 psi) | 75 GPa (11 x 106 psi) |
| Tensile Strength | 790 to 910 MPa (120 to 130 x 103 psi) | 930 to 1530 MPa (130 to 220 x 103 psi) |
FAQ
| Frequently Asked Question | Values |
|---|---|
| Inconel 718 Density | 0.296 lb/in3 (Solution Treated) |
| Inconel 625 Yield Strength | ≥ 414 MPa |
| Yield Strength Of Inconel 718 | 827 MPa |
| Inconel 625 Hardness | 84 |
| Inconel 718 Thermal Conductivity | 0-100 °C (6.5 W/m.K) |
| Inconel 718 Rockwell Hardness | 24 |
| Inconel 625 & 718 Melting Point | 1330°C & 1370-1430°C |
| Is Inconel Stronger Than Titanium | No |
| Is Inconel 718 Magnetic | No |
Conclusion
Gnee Steel is a supplier of Inconel 625 and Inconel 718 in tubes, pipes, plates, strips, plates, round bars, flat bars, forged billets, hexagons, wire and extrusions. We work with steel mills to provide customers with 625 alloy that meets or exceeds many leading industry standards, including ASTM, ASME, SAE, AMS, ISO, DIN, EN and BS standards.
Gnee Steel stocks and sells Inconel 625 and Inconel 718 tubes, pipes, plates, strips, plates, round bars, flat bars, forged billets, hexagons, wire and extrusions. Feel free to contact us for a quote at ss@gneesteel.com
