What Are The Types Of Inconel Nuts?

What Are The Types Of Inconel Nuts?

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What is Inconel?

The Inconel metal is an amalgamation of the nickel-chromium- molybdenum alloys making them sturdy and highly resistant to elevated temperatures and corrosion. Due to its high thermal stability, Inconel is suitable for being used in service temperatures that range from the coldest upto 2200°F. The Inconel melting point ranges between 2,350°F and 2,460°F (1,290°C and 1,350°C).

Inconel has a high alloy content. This is also why the alloy can withstand varying levels of severe corrosive environments. The Inconel alloy is hardly affected in mild environments like seawater, alkaline, or neutral salts. However, in highly corrosive environments, the combination of nickel and chromium gives it the resistance it needs against oxidizing chemicals. On the other hand, nickel and molybdenum give the alloy resistance to nonoxidizing environments.

Inconel nuts as well belong to the nickel-molybdenum-chromium alloy family. Inconel nuts are most preferred in industries like aerospace, marine, oil and gas, along with chemical processing, and electronics. This is due to their excellent characteristics temperature stability and corrosion resistance.

Inconel 625 and Inconel 718 are two of the most common grades of Inconel nickel alloy, but not limited to just them. To receive more insight on the different grades of Inconel Nuts, take a look at the list below.

Common Inconel Nut Grades

Some of the common Inconel nuts in use today are as follows-

  1. Inconel 600:

    This Inconel alloy 600 is a chromium-nickel that possesses good resistance towards carburization and oxidation through temperatures at 2000°F. Inconel 600 has been available for use since a long time, especially in the heat treating industry. Other than that Inconel 600 also possesses functional resistance to dry Chlorine (Cl2) and Hydrochloric acid (HCl) gases at relatively high temperatures.

  2. Inconel 601:

    The alloy is favorably resistant to oxidation even under harsh thermal cycling. Inconel 601 possesses high ductility even after long exposure. Along with that Inconel 601 is also resistant to hot corrosion under oxidizing conditions.

  3. Inconel 625:

    It can be safely said that this alloy is the hardest working alloy of the Inconel family. It also is one of the most common grades of Inconel available. Inconel 625 displays elevated creep-rupture strength with resistance to oxidation at upto 1800°F (982°C). No wonder, Inconel alloy 625 is used for applications involving scrubber environments, hot seawater, and reducing acids. Additionally, Inconel 625 is exceptionally resistant to highly corrosive environments as well as to pitting and crevice corrosion.

  4. Inconel 686:

    This alloy of the Inconel family has been designed to deliver superior resistance to corrosion pertaining to various environments. Inconel 686 is mostly used in environments that are encountered in industries like the treatment of industrial and municipal waste, pollution control, chemical processing, and pulp and paper production.

  5. Inconel 718:

    This is one of the most common grades of hardenable Inconel, which is twice as strong as Inconel 625. The Inconel 718 alloy combines its high strength and exceptional corrosion resistance at elevated temperatures for best performance. Inconel 718 is mostly used in rocket motors, gas turbines, nuclear reactors, spacecraft, pumps, and tooling.

  6. Inconel 725:

    The Inconel alloy 725 is a hardenable alloy that possesses corrosion resistance similar to Inconel 625. Inconel 725 is twice as strong as annealed Inconel 625, which is developed by using heat treatment to achieve high ductility and toughness. Inconel 725 is resistant to stress corrosion cracking and hydrogen embrittlement.

  7. Inconel X750:

    Inconel X-750 is a type of precipitation hardened alloy which is recognized for its resistance to corrosion and oxidation at high temperatures of upto 1300°F. Inconel X-750 is similar to Inconel 600 with the exception that the former is precipitation hardenable with the addition of aluminum and titanium.


These were some of the most common grades of Inconel that are used in most industries today. Inconel is an expensive material that is best reserved for the right use conditions where other materials won’t work as well. Just remember, the superalloy is better for heat treating applications and other high-temperature processes.

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