Whether you are a supplier or a end user of Inconel alloys, you may face challenges when deciding between Incoloy Alloy 825 and Inconel Alloy 718 or advising customers on material selection.
Both Incoloy Alloy 825 and Inconel Alloy 718 are superalloys known for their exceptional properties.
This article will compare alloy 825 and alloy 718 across various aspects, providing you with a clearer understanding of these two alloys.
INCOLOY® alloy 825 (UNS N08825 / W.Nr. 2.4858) is a nickel-iron-chromium alloy with additions of molybdenum, copper, and titanium. The alloy’s chemical composition is designed to provide exceptional resistance to many corrosive environments.
The nickel content is sufficient for resistance to chloride-ion stress-corrosion cracking. The nickel, in conjunction with the molybdenum and copper, also gives outstanding resistance to reducing environments such as those containing sulfuric and phosphoric acids.
The molybdenum also aids resistance to pitting and crevice corrosion. The alloy’s chromium content confers resistance to a variety of oxidizing substances such as nitric acid, nitrates and oxidizing salt. The titanium addition serves, with an appropriate heat treatment, to stabilize the alloy against sensitization to intergranular corrosion.
The resistance of INCOLOY alloy 825 to general and localized corrosion under diverse conditions gives the alloy broad usefulness. Applications include chemical processing, pollution control, oil and gas recovery, acid production, pickling operations, nuclear fuel reprocessing, and handling of radioactive wastes. Applications for alloy 825 are similar to those for INCOLOY alloy 020.
What is Inconel Alloy 718?
INCONEL® alloy 718 (UNS N07718 / W.Nr. 2.4668) is a high-strength, corrosion-resistant nickel chromium material used at -423° to 1300°F. The age-hardenable alloy can be readily fabricated, even into complex parts. Its welding characteristics, especially its resistance to postweld cracking, are outstanding.
Incoloy Alloy 825 vs Inconel Alloy 718 Chemical Composition
Here’s a comparison table for the chemical composition of alloy 825 and 718:
Incoloy Alloy 825 vs Inconel Alloy 718 Corrosion Resistance
Choosing between Incoloy Alloy 825 and Inconel Alloy 718 depends on the specific environmental conditions and temperature requirements of your application.
Incoloy 825 is preferable for reducing acid environments, while Inconel 718 is superior for high-temperature and oxidizing conditions.
Incoloy Alloy 825 vs Inconel Alloy 718 Mechanical Behavior
Incoloy 825 Mechanical Properties
| Density | Melting Point | Tensile Strength | Yield Strength (0.2%Offset) | Elongation |
| 8.14 g/cm3 | 1400 °C (2550 °F) | 690-1000Mpa | 330-880Mpa | 45% – 15% |
Inconel 718 Mechanical Properties
| Density | Melting Point | Tensile Strength | Yield Strength (0.2%Offset) | Elongation |
| 8.28 g/cm3 | 1390 °C (2540 °F) | 910Mpa | 550Mpa | 25% |
Incoloy Alloy 825 vs Inconel Alloy 718 Physical Properties
| Incoloy 825 | Inconel 718 | |
|---|---|---|
| Density, g/cm³ | 8.14 | 8.28 |
| Density, lb/in.³ | 0.305 | 0.296 |
| Melting Range, °F | 2550 | 2300-2437 |
| Melting Range, °C | 1400 | 1260-1336 |
| Permeability at 200 oersted (15.9 kA/m) | 1.005 | 1.0006 |
| Curie Temperature, °F | <-320 | -170 |
| Curie Temperature, °C | -196 | -112 |
Incoloy Alloy 825 vs Inconel Alloy 718 Application
The resistance of INCOLOY alloy 825 to general and localized corrosion under diverse conditions gives the alloy broad usefulness. Applications include chemical processing, pollution control, oil and gas recovery, acid production, pickling operations, nuclear fuel reprocessing, and handling of radioactive wastes.
The ease and economy with which INCONEL alloy 718 can be fabricated, combined with good tensile, fatigue, creep, and rupture strength, have resulted in its use in a wide range of applications. Examples of these are components for liquid fueled rockets, rings, casings and various formed sheet metal parts for aircraft and land-based gas turbine engines, and cryogenic tankage. It is also used for fasteners and instrumentation parts.
Incoloy Alloy 825 vs Inconel Alloy 718 Main Standards
Here’s a comparison table for the standards of alloy 825 and Inconel alloy 718:
Incoloy Alloy 825 vs Inconel Alloy 718 Cost
In general, Inconel 718 alloy is more expensive than Inconel 825 due to its higher chromium content. However, the price difference between the two alloys will vary depending on the specific composition and supplier.
Conclusion
The resistance of INCOLOY alloy 825 to general and localized corrosion under diverse conditions gives the alloy broad usefulness.
Inconel 718, a precipitation-hardened alloy, is characterized by its exceptionally high strength.
Each alloy serves its specific purposes and cannot substitute for the other.
HZW supplies both Incoloy 825 and Inconel 718 products, adhering to standard solution treatment or aging treatment processes. For material purchase inquiries, please feel free to contact us.
