Inconel 625 (UNS N06625 / W.Nr.2.4856)

Approximate Brand:

Chemical constituents of Inconel 625:

Physical properties of Inconel 625:

Minimum mechanical properties of Inconel 625 at room temperature:

The alloy has the following characteristics:

1. Excellent corrosion resistance to various corrosive media in oxidation and reduction environments

2. Excellent resistance to pitting and crevice corrosion, and no stress corrosion cracking due to chloride

3. Excellent corrosion resistance to inorganic acids, such as nitric acid, phosphoric acid, sulfuric acid, hydrochloric acid and mixed acid of sulfuric acid and hydrochloric acid.

4. Excellent corrosion resistance to mixed inorganic acid solutions

5. When the temperature reaches 40 C, it shows good corrosion resistance in hydrochloric acid solutions of various concentrations.

6. Good workability and weldability, no post-weld cracking sensitivity

7. Manufacturing Certification of Pressure Vessels with Wall Temperature ranging from -196 to 450 C

8. Accredited by NACE Standard of American Association of Corrosion Engineers (MR-01-75) to meet the highest standard grade VII for use in acid gas environment

Metallographic structure of Inconel  625:

625 is a face-centered cubic lattice structure. Carbon particles and unstable quaternary phases will be precipitated and transformed into stable Ni3 (Nb, Ti) oblique lattice phase after holding at 650 C for a long time. The molybdenum and niobium components in nickel-chromium matrix after solution strengthening will improve the mechanical properties of the material, but the plasticity will be reduced.

Corrosion resistance of Inconel 625:

625 alloy exhibits excellent corrosion resistance in many media. It has excellent pitting resistance, crevice corrosion, intergranular corrosion and corrosion resistance in chloride medium. It has good corrosion resistance to inorganic acids, such as nitric acid, phosphoric acid, sulfuric acid, hydrochloric acid, etc. It also has alkali and organic acid corrosion resistance in oxidation and reduction environment. Effective resistance to chloride reduction stress corrosion cracking. There is almost no corrosion in seawater and industrial gas environment, and it has high corrosion resistance to seawater and salt solution, as well as at high temperature. There is no sensitivity during welding. It is resistant to carbonization and oxidation in both static and cyclic environments and to chlorine-containing gas corrosion.

Inconel 625 has a wide range of applications:

Low carbon alloy 625 after softening annealing is widely used in chemical process industry. It has good corrosion resistance and high strength, which makes it a thinner structural component. 625 alloy can be used in contact with seawater and withstand high mechanical stress. Typical applications:

1. Components of organic chemical processes containing chloride, especially when acid chloride catalysts are used

2. Cookers and bleaching tanks for pulp and paper industry

3. Absorption tower, reheater, flue gas inlet baffle, fan (damp), agitator, guide plate and flue duct in flue gas desulfurization system, etc.

4. Equipment and components for the manufacture of acid gas environments

5. Reaction Generator of Acetic Acid and Acetic Anhydride

6. Sulfuric acid condenser