Properties of alloy 625

Alloy 625 has high resistance to corrosion in both acidic and alkaline environments. It exhibits excellent resistance to pitting corrosion and stress corrosion cracking. Inconel 625 is frequently used in seawater environments, chemical processes, the nuclear industry and aerospace applications. For welding Alloy 625, CEWELD® NiCro 625 and similar alloys like CEWELD® NiCrMo 622 are typically used as filler materials. These materials provide similar properties and ensure good corrosion and oxidation resistance in the weld zone. TIG welding and MIG welding are often employed.

Typical chemical composition in %

Ni: 58
Cr: 20-23
Mo: 8-10
Fe: 5
Nb: 3.15-4.15

Small amounts of other elements like titanium, aluminum, manganese, silicon, carbon, phosphorus, sulfur, and copper.

Corrosion Resistance of Alloy 625:

General Corrosion Resistance: Alloy 625 offers excellent resistance to general corrosion in various environments, including seawater, freshwater, and atmospheric conditions.

High-Temperature Oxidation and Carburization Resistance: Alloy 625 displays exceptional resistance to oxidation and carburization at elevated temperatures, making it suitable for high-temperature applications.

Acidic Corrosion Resistance: It has good resistance to corrosion by acids, such as sulfuric acid and phosphoric acid, as well as hydrochloric and hydrofluoric acids in certain concentrations and conditions.

Alkaline Corrosion Resistance: Alloy 625 also resists corrosion by alkaline solutions, including sodium hydroxide (caustic soda) and potassium hydroxide.

Chloride-Ion Stress Corrosion Cracking (SCC) Resistance: Alloy 625 exhibits high resistance to chloride-ion stress corrosion cracking, making it suitable for applications in chloride-rich environments, such as marine and offshore industries.

Pitting and Crevice Corrosion Resistance: Alloy 625 has good resistance to pitting and crevice corrosion, which are localized forms of corrosion often encountered in chloride-containing environments.

Alloy 625 finds widespread applications in industries such as chemical processing, aerospace, marine engineering, oil and gas production, and nuclear power generation, where its corrosion resistance and high-temperature properties are crucial.