Incoloy 825

Incoloy 825 is a titanium stabilized, fully austenitic nickel-iron-chromium alloy with additions of copper and molybdenum.Incoloy 825 is a versatile engineering alloy that is resistant to acid and alkali metal corrosion in both oxidizing and reducing environments.

Foreign Name Incoloy 825 Application Areas Air heat exchangers in petroleum refining Alloy Properties Good resistance to stress corrosion cracking Chemical Composition Nickel Ni: 38-46

Alloy Overview

The high nickel content gives the alloy effective resistance to stress corrosion cracking. Corrosion resistance is good in a variety of media such as sulfuric, phosphoric, nitric and organic acids, and alkali metals such as sodium hydroxide, potassium hydroxide and hydrochloric acid solutions.Incoloy 825's high overall performance is demonstrated by the variety of corrosive media in the nuclear combustion dissolver, such as sulfuric, nitric, and sodium hydroxide are handled in the same equipment.

Similar grades

NS142 (China), NC21FeDu (France), W.N r.2.4858 NiCr21Mo (Germany) NA16 (UK)

Incoloy825, UNS NO8825 (USA) NiFe30Cr21Mo3 (ISO)

Chemical Composition

Nickel Ni: 38-46

Chromium Cr: 19.5-23.5

Iron Fe: remainder

Carbon C: ≤0.025

Manganese Mn: ≤1.0

Silicon Si: ≤0.5

Molybdenum Mo: 2.5-3.5

Copper Cu: 1.5-3.0

Cobalt Co: ≤1.0

Aluminum Al: ≤0.2

Titanium Ti: 0.6-1.2

Alloy Characteristics

Good resistance to stress corrosion cracking performance

●Good resistance to pitting and crevice corrosion

Good resistance to oxidation and non-oxidizing thermo-acidic properties

Good mechanical properties at room temperature and up to 550°C

Certified for the manufacture of pressure vessels up to 450°C

Alloy Application Areas

Incoloy 825 is widely used in a variety of industrial applications where the service temperature does not exceed 550°C.

Typical applications are:

●Heating pipes, vessels, baskets and chains for sulfuric acid pickling plants.

●Heat exchangers for seawater cooling, piping systems for marine products, and piping for sour gas environments.

●Heat exchangers, evaporators, washing and impregnation tubes in phosphoric acid production.

●Air heat exchangers in petroleum refining

●Food engineering

●Chemical processes

●Flame retardant alloys for pressurized oxygen applications