Inconel 625

Inconel 625 Alloy

Inconel 625 is a nickel-based superalloy with excellent resistance to corrosion and oxidation.

It is used in a variety of applications that require high strength, such as aerospace and power generation, as well as in chemical processing and marine environments.

Inconel 625 has a high melting point and is resistant to corrosion in a wide range of media, including seawater and acidic environments. It is also resistant to stress corrosion cracking and has good fatigue strength.

The alloy has good weldability and can be readily fabricated by a variety of methods, including hot and cold working, as well as machining.

Inconel 625

Inconel 625 Material Standards & Specification

Inconel 625 UNS Number is UNS N06625. ISO Number of Inconel 625 is 2.4856. Inconel 625 material standard and specification for delivery are:

  • ASTM B 366, 443, 446, B564, B704, B751.
  • SAE- AMS 5666, 5837, 5599, 5581.
  • ISO 9723, ISO 9725, ISO 6208, ISO 6207.

The EN Designation of Inconel 625 is 2.4856 – NiCr22Mo9Nb and ISO is NC22DNb.

Inconel 625 chemical composition

The chemical composition of Inconel 625 is as follows:

  • Nickel (Ni): 58% min
  • Chromium (Cr): 20-23%
  • Iron (Fe): 5.0% max
  • Manganese (Mn): 0.5% max
  • Carbon (C): 0.10% max
  • Silicon (Si): 0.50% max
  • Molybdenum (Mo): 8 – 10%
  • Niobium (Nb): 3.15-4.15%
  • Titanium (Ti): 0.40% max
  • Aluminum (Al): 0.40% max
  • Cobalt (Co): 1.0% max

Please note that these are the typical ranges for the alloy and that the exact composition may vary slightly depending on the specific manufacturer and production process.

Inconel 625 Mechanical Properties

Inconel 625 has excellent mechanical properties, including high strength and good toughness. Some of the key mechanical properties of Inconel 625 at room temperature are:

  • Ultimate tensile strength: 120-160 Ksi,
  • Yield strength: 60-110 Ksi,
  • Elongation: 30-60%.
  • Hardness: 145-240 HB
Inconel-625-mechanical-properties

Inconel 625 also has good fatigue strength and is resistant to stress corrosion cracking. It has a relatively low modulus of elasticity, which can make it more susceptible to deformation under load. However, its high strength and toughness help to compensate for this.

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It is important to note that the mechanical properties of Inconel 625 can be affected by factors such as temperature, strain rate, and the condition of the material (e.g., annealed, cold worked, etc.).

Inconel 625 Hardness

Inconel 625 has a Brinell hardness of approximately 145-240 HB or 29 HRC.

Inconel 625 Physical Properties

Inconel 625 is a nickel-based superalloy with excellent resistance to corrosion and oxidation. Some of the key physical properties of Inconel 625 are:

  • Density: 8.4 g/cm³ (0.305 lb/in³)
  • Melting point: 1,290-1,350 °C (2,350-2,460 °F)
  • Thermal expansion coefficient: 7.1 µinch/inch °F,
  • Thermal conductivity: 9.8 W/mK (68 BTU in/hr ft² °F)

What is Inconel 625 used for?

Inconel 625 is used in a variety of applications that require high strength and corrosion resistance, such as:

  • Aerospace: Inconel 625 is used in the manufacture of aircraft parts, including exhaust systems, skin and structural components, and hydraulic systems. It is also used in the construction of rocket engines and other high-performance aerospace applications.

  • Power generation: Inconel 625 is used in the manufacture of components for power generation systems, including gas turbine blades, combustion liners, and steam turbine blades. It is also used in the construction of nuclear reactors and other high-temperature power generation systems.

  • Chemical processing: Inconel 625 is resistant to corrosion in a wide range of media, including acidic environments, making it suitable for use in chemical processing applications. It is used in the manufacture of equipment for the chemical, petrochemical, and pharmaceutical industries, such as heat exchangers, piping, and pumps.

  • Marine: Inconel 625 is resistant to corrosion in seawater and is used in the construction of marine equipment, including propellers, shafts, and hulls for ships and submarines.
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  • Other: Inconel 625 is also used in a variety of other applications, including springs, seals, and fasteners. It is also used in the construction of sporting goods, such as golf club heads and bicycle frames.

Read more: Inconel 625 Welding.

can you heat treat Inconel 625

Yes, Inconel 625 can be heat treated. Heat treatment is a process that involves heating and cooling a material to alter its microstructure and improve its mechanical properties.

The specific heat treatment process used for Inconel 625 will depend on the desired properties and the intended application of the material.

Inconel 625 can be heat treated using a variety of methods, including annealing, normalizing, and solution treating.

The annealing temperature for Inconel 625 is typically between 2000-2200°F.


Can you passivate Inconel 625?

Yes, Inconel 625 can be passivated, if required to improve its corrosion resistance.

How hard is Inconel 625?

In general, Inconel 625 has a Brinell hardness of approximately 145-240 HB, a Rockwell C hardness of approximately 29 HRC.

Inconel 625 annealing temperature

The annealing temperature for Inconel 625 is typically between 2000-2200°F.

Is Inconel 625 a stainless steel?

No, Inconel 625 is not a stainless steel. Inconel 625 is a nickel-based superalloy with excellent resistance to corrosion and oxidation. It is composed primarily of nickel, with smaller amounts of chromium, iron, molybdenum, niobium, and other elements.
While Inconel 625 has excellent corrosion resistance and is often used in applications that require corrosion resistance, it is not a stainless steel. It is a superalloy that is specifically designed for high-strength and corrosion-resistant applications, such as aerospace and power generation.

Is Inconel 625 magnetic?

No, Inconel 625 is non-magnetic alloy material. Due to its austenitic microstructure nickel is not a ferromagnetic material.

Is Inconel 625 austenitic?

Yes, Inconel 625 is an austenitic nickel-based superalloy. Austenitic alloys are characterized by their face-centered cubic crystal structure, which gives them good ductility and corrosion resistance. Inconel 625 is composed primarily of nickel, with smaller amounts of chromium, iron, molybdenum, niobium, and other elements.

Is Inconel 625 nace compliant?

Inconel 625 is typically NACE compliant. NACE (National Association of Corrosion Engineers) is an organization that sets standards and guidelines for the prevention of corrosion in a variety of industries.

Is Inconel 625 non-ferrous?

Yes, Inconel 625 is a non-ferrous material. Non-ferrous materials are materials that do not contain iron and are not magnetic.

Is Inconel 625 ferrous?

No, Inconel 625 is not a ferrous alloy. It contains predominately Nickel alloy making it a non-ferrous alloy.

What is Inconel 625 ASTM Standard?

Inconel 625 ASTM Standard are ASTM B 446, B 466, B 564, B 443, B 444, B 829, B 775 and B 366.

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