Inconel X-750 – Composition, Properties and Applications of Inconel X-750 Nickel-Chromium Alloy by Alloy Wire International

Topics Covered


Inconel X-750 – Nickel-Chromium Alloy

Chemical Composition of Inconel X-750

Typical Properties of Inconel X-750

Properties of Supplied Materials and Heat Treated Materials

Relevant Standards

Equivalent Materials

Applications of Inconel X-750


Alloy Wire International Ltd. is a U.K. wire manufacturer specialising in the production of high performance alloys, mainly Nickel Alloys, but including Cobalt and Titanium Alloys.

These alloys might be used in any environment that requires resistance to heat and corrosion but where the mechanical properties of the metal must be retained.

Inconel X-750 – Nickel-Chromium Alloy

Inconel X-750 is a Nickel-Chromium alloy made precipitation hardenable by additions of Aluminium and Titanium, having creep-rupture strength at high temperatures to about 700°C (1290°F).

It is widely used for high temperature conditions but is not as strong as Nimonic 90.

Chemical Composition of Inconel X-750

The compositional range for Inconel X-750 is provided in the table below.




70 % min


14 – 17 %


5 – 9 %


2.25 - 2.75 %


0.4 - 1.0 %


0.7 - 1.2 %

Typical Properties of Inconel X-750

Typical properties of Inconel X-750 are covered in the following table.





8.28 g/cm3

0.299 lb/in3

Melting point



Co-Efficient of Expansion

12.6 μm/m.°C


7.0x10-6 in/in.°F


Modulus of rigidity

75.8 kN/mm2

10994 ksi

Modulus of elasticity

*218.0 kN/mm2

31619 ksi

**212.4 kN/mm2

30806 ksi

***213.7 kN/mm2

30995 ksi

* Spring Temper + Aged **Spring Temper + 3 Part Heat Treated *** No.1 Spring Temper + Aged

Properties of Supplied Materials and Heat Treated Materials

Condition of Supply

Heat Treatment (After Forming)

Spring Temper

Age harden at 650°C (1200°F) for 4 hours and air cool.

Spring Temper

3 Part Heat Treatment:

*1. Solution Anneal at 1150°C (2100°F) for 2 hours and air cool

2. and Stabilise at 843°C (1550°F) for 24 hours and air cool

3. and Age harden at 704°C (1300°F) for 20 hours and air cool.

No.1 Spring temper

Age harden at 730°C (1350°F) for 16 hours and air cool.


Approx Tensile Strength

Approx Service Temp.


800 - 1000 N/mm2

116 - 145 ksi

Spring Temper

1100 - 1500 N/mm2

159 - 217 ksi


Spring Temper + Aged

1350 - 1750 N/mm2

196 - 254 ksi

-200 up to 370 °C

-330 up to 700°F

Spring Temper + 3 Part heat treated

1100 - 1250 N/mm2

159 - 181 ksi

-200O up to 550 °C

-330 up to 1020°F

No.1 Spring Temper

900 - 1150 N/mm2

130 - 167 ksi

No.1 Spring Temper + Aged

1300 - 1450 N/mm2

188 - 210 ksi

-200O up to 550°C

-330 up to 1020°F

*for diameters below 1.00mm contact AWI technical department.

Relevant Standards

Inconel X-750 is covered by the following standards:

         AMS 5667

         AMS 5699 (Spring temper)

         AMS 5698 (No.1 Spring Temper)

         ASTM B637

         BS HR 505

Equivalent Materials

Inconel X-750 is the tradename of Special Metals Group of Companies and equivalent to:

         W.NR 2.4669

         UNS N07750

         AWS 014

Applications of Inconel X-750

Inconel X-750 typically finds application in:

         Nuclear reactors

         Gas turbines

         Rocket engines

         Pressure vessels

         Aircraft structures.



Source: Alloy Wire International


For more information on this source please visit Alloy Wire International.


Date Added: May 2, 2008 | Updated: Jun 11, 2013
  1. Deepak Kulange Deepak Kulange India says:

    Is it use for cyogenics fuel tanks?

  2. Acharya NK Acharya NK India says:

    How to avoid cracks in springs after cold forming ?

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