Inconel 625 is a high-performance nickel-chromium alloy known for its excellent fatigue, thermal-fatigue strength, and outstanding resistance to oxidation and corrosion, particularly in extreme environments such as high-temperature and corrosive atmospheres. Below is the typical composition of Inconel 625 (UNS N06625):
Inconel 625 Composition (Nominal Values):
Nickel (Ni): 58.0% – 63.0%
Chromium (Cr): 20.0% – 23.0%
Molybdenum (Mo): 8.0% – 10.0%
Iron (Fe): 5.0% (maximum)
Niobium (Nb): 3.15% – 4.15%
Titanium (Ti): 0.4% – 1.0%
Aluminum (Al): 0.4% (maximum)
Cobalt (Co): 1.0% (maximum)
Manganese (Mn): 0.5% (maximum)
Silicon (Si): 0.5% (maximum)
Carbon (C): 0.1% (maximum)
Sulfur (S): 0.015% (maximum)
Phosphorus (P): 0.015% (maximum)
Key Characteristics:
Nickel: Provides overall corrosion resistance and strength at high temperatures.
Chromium: Enhances resistance to oxidation and corrosion, particularly in high-temperature, oxidative environments.
Molybdenum: Improves resistance to pitting, crevice corrosion, and stress corrosion cracking in both acidic and marine environments.
Niobium: Provides solid solution strengthening and helps maintain the alloy's strength at elevated temperatures.
Titanium: Helps stabilize the alloy and improve its resistance to high-temperature oxidation.
Inconel 625 is often used in applications where resistance to aggressive environments is crucial, such as in aerospace, chemical processing, and marine applications. It is particularly favored for its resistance to sulfuric acid, hydrochloric acid, and other aggressive chemicals, as well as its ability to withstand temperatures up to 2000°F (1093°C).
