Inconel® Alloy X750

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Applications

Springs operating from cryogenic temperatures up to 1300°F (704°C), fasteners and components requiring resistance to high temperature and corrosive environments.

Description

Inconel^® X750 is a precipitation hardenable Nickel-Chromium alloy with high strength at temperatures up to 1300°F (704°C) and oxidation resistance up to 1800°F (982°C). Inconel^® X750 offers excellent resistance to relaxation and as a result it is widely used for springs operating at elevated temperatures.

Industries Supplied

Oil & Gas Extraction and Processing, Nuclear, Aerospace, Power Generation and Automotive

Nominal Composition

Ni: 70.0 min
Cr: 14.0 – 17.0
Fe: 5.0 – 9.0
Ti: 2.25 – 2.75
Al: 0.40 – 1.0
Cb (Nb): 0.70 – 1.20
Mn: 1.0
Si: 0.50 max
C: 0.08 max
S: 0.01 max
Cu: 0.5 max

Physical Properties

Density: 0.299 lb/in³, (8.28 g/cm³)

Modulus of Elasticity (E):
At 70°F (20°C): 31.0 x 106 psi (214 GPa)
At 1000°F (538°C): 26.7 x 106 psi (184 GPa)

Modulus of Rigidity (G):
At 70°F (20°C): 12.0 x 10⁶ psi (82.7 GPa)

Coefficient of Expansion:
7.8 µin/in.-°F (70°F to 1000°F)
14.5 µm/m-°C (20°C to 538°C)

Electrical Resistivity: 20.1 µΩ.in, (122 µΩ.cm)

Thermal Conductivity: 83 Btu-in/ft²hr-°F, (12.0 W/m-K)

Applicable Specifications

Wire & Bar: AMS 5698, AMS 5699, AMS 5778, NACE MR0175 (ISO 15156-3), ASTM B637, AMS 5667, AMS 5668, AMS 5670

Typical Mechanical Properties – Spring Applications

• Annealed
  • Heat Treatment: 2000 – 2200°F (1093 – 1204°C)
  • Tensile Strength: 130 ksi max; (896 MPa) max
• No.1 Temper
  • Heat Treatment: As supplied condition.
  • Tensile Strength: 130 – 165 ksi; (896 – 1138 MPa)
• No.1 Temper + Aged
  • Heat Treatment: After spring coiling. Age: 1350°F (732°C) for 16 hours.
  • Tensile Strength: 165 – 220 ksi (1138 – 1517 MPa)
  • Suggested Operating Conditions: Optimum resistance to relaxation at temperatures up to 1000°F (538°C) with moderate or low stresses.
• Spring Temper
  • Heat Treatment: As supplied condition.
  • Tensile Strength: 160 – 220 ksi; (1103 – 1517 MPa)
• Spring Temper + Aged
  • Heat Treatment: After spring coiling. Age: 1200°F (649°C) for 4 hours.
  • Tensile Strength: 180 – 250 ksi; (1241-1793 MPa)
  • Suggested Operating Conditions: Optimum stress and low relaxation at temperatures up to 700°F (371°C)
• Spring Temper + Solution + Aged (3 Step Heat treatment)
  • Heat Treatment: After spring coiling. Solution Heat Treat: 2100°F (1149°C) for 2 hours and air cool. Age Harden at 1550°F (843°C) for 24 hours and air cool. Reheat to 1300°F(704°C) for 20 hours and air cool.
  • Tensile Strength: 145 – 190 ksi; (1000-1310 MPa)
  • Suggested Operating Conditions: Optimum resistance to relaxation at temperatures in the range 1000 – 1300°F (538 – 704°C).

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Inconel^® is a registered trademark of the Special Metals Corporation group of companies.

For further information Contact:

Contact Us
Phone: 1 847 695 1900
Elgiloy Specialty Metals – Wire Products
356 N.Cross Street
Sycamore, IL 60178 USA

Limitation of Liability and Disclaimer of Warranty:

• The content in these data sheets is provided primarily by third-party melting mills and is provided for reference only.  It is not intended for engineering or design.
• Applications may be discussed, however, Elgiloy Specialty Metals, a Division of Combined Metals Company LLC, does not recommend or endorse any material for any particular end use or application.
• The data included in this data sheet are typical values and may vary.
• Elgiloy Specialty Metals, a Division of Combined Metals Company LLC, makes no representations or warranties, express or implied, as to the accuracy, completeness, condition, suitability, performance, fitness for a particular purpose, or merchantability of any information contained in any data sheet.

In no event will Elgiloy Specialty Metals, a Division of Combined Metals Company LLC, be liable for any damages whatsoever arising from the use of the information included in the data sheets.