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List of Alloys & profiles

List of Alloys & profiles

Alloy Wire International

Datasheet: Incoloy® 825

Incoloy® 825

Incoloy® 825 is a Nickel-Iron-Chromium alloy with additions of Molybdenum and Copper. It has excellent resistance to both reducing and oxidising acids, to stress-corrosion cracking and to localised pitting. It is also especially resistant to sulphuric and phosphoric acids. Alongside Inconel® 625, Incoloy® 825 is one of the most important nickel alloys for the oil and gas industry. Thanks to the balance of elements, it offers exceptional resistance to chloride stress corrosion cracking, as well as crevice corrosion and general corrosion.

Incoloy® 825 is also known as Nicrofer 4221, Superimphy 82 and Ferrochronin 825.

Available in all profile options

Incoloy® 825 - Alloy Wire International 1

Key Features

Incoloy® 825 offers the following key features:

Resistant to reducing environments such as those containing sulphuric and phosphoric acids
Resistant to a variety of oxidising substances such as nitric acid and nitrates
Resistant to chloride-ion stress corrosion cracking and, pitting & crevice corrosion
Good for chemical processing

Typical Applications

Incoloy® 825 is known to be suitable for the following applications:

Chemical Processing
Nuclear Fuel Reprocessing
Acid Production
Pickling Equipment


W.Nr 2.4858
UNS N08825
AWS 022


BS 3075 NA 16
BS 3076 NA 16
ISO 15156-3
(NACE MR 0175)

Chemical Composition

The chemical composition of Incoloy® 825 is indicated in the table below:

ElementMin %Max %

Alloy Details

Incoloy® 825 density, melting point, coefficient of expansion, and modulus of elasticity is indicated in the table below:

DensityMelting PointCoefficient of ExpansionModulus of RigidityModulus of Elasticity
8.14 g/cm³1400 °C14.0 μm/m °C (20 – 100 °C)75.9 kN/mm²196 kN/mm²
0.294 lb/in³2550 °F7.8 x 10-6 in/in °F (70 – 212 °F)11009 ksi28428 ksi

Heat treatment of finished parts

The typical heat treatment of Incoloy® 825:

Condition as supplied by AWITypeTemperatureTimeCooling
Annealed or Spring TemperStress Relieve450 – 470 °C (840 – 880 °F)0.5 – 1 HrAir


The typical mechanical properties of Incoloy® 825:

Approx. tensile strength<800 N/mm²<116 ksi
Approx. operating temperature depending on load** and environment-100 to +250 °C-145 to +480 °F
Spring Temper
Approx. tensile strength800 – 1100 N/mm²116 – 159 ksi
Approx. operating temperature depending on load** and environment-100 to +250 °C-145 to +480 °F

The above tensile strength ranges are typical. If you require different please ask.

*Trade name of Special Metals Group of Companies