Nickel Alloy Fasteners Specification

Nickel Alloy Fasteners are generally used in high temperature conditions due to its tendency to preserve high tensile strength at elevated temperatures.
The unique combination nickel chromium and molybdenum provides excellent resistance to corrosion in acidic environments and extremely saline solutions. Monel 400 is the most commonly used nickel alloy for cold forged fasteners.

Nickel Alloy Fasteners Properties

Typically Nickel Alloy Fasteners are implemented at high temperatures where other stainless steel bolts and duplex steel bolts fails in withholding both the temperature and physical properties.

Extremely high temperature applications which include heating furnaces both induction and melting, exhaust air systems, chimneys, rocket engines,automobile and commercial engines, aircrafts, blast furnace, valve components, submersible pumps, gas turbines and many other high heating equipment’s.

Inconel 718,nickel alloy 718,incoloy 718 fasteners like bolts nuts and washers are amongst the widely used high temperature fasteners.

Trade names like Inconel bolts,monel bolts ,hastelloy bolts with combinations of Inconel nuts and washers, monel nuts and washers ,hastelloy nuts and washers are generic terms used in the fasteners market for saline applications where high corrosion resistance is required.

Salt-water applications like pressure vessels, water purification plants, sewage line, chemical plants, and offshore industries, rigging facilities are amongst the few areas of nickel alloy fasteners for corrosive environments.

Trade names like nimonic 80a bolts, nimonic 90a bolts with combinations if nimonic 80a nuts and washers, nimonic 90a nuts and washers respectively have been established to use nickel alloy fasteners for its unique property of creep resistance under highest levels of stress and high temperature conditions.

Applications include major from the navy and defense sectors using aircraft’s with exhaust valves and rotatory turbines.

Apart from the above applications of nickel alloy fasteners there are many other exceptional benefits like low expansion at high temperatures, constant wear resistance, extremely tough and fine-grained structure, and ease of formability at dedicated temperatures.

More than 60 different nickel alloy grade bolts, nuts, washers and studs are manufactured at TorqBolt to serve most crucial sectors like defense, space research centers, offshore industries, chemical plants are as listed below.

Equivalent Designation
ASTM AISI UNS British Standard En NameWerkstoff No. Swedish(SS) JIS(SUS) Werkstoff No.

Monel Fasteners

Monel Fasteners are nickel alloy fasteners with 29-33 % copper content also known by the trade name Nickel-Copper Alloys. It has high corrosion resistance to acids and alkalis with high mechanical properties and ductility. Being very difficult to machine , Monel Fasteners can be hardened and available in different variation like Monel 400, Monel 500 etc Monel 500 has additions of aluminum and titanium, which adds toughness to monel 400.

Applications: Monel fasteners are used for aerospace applications, oil refining and production, marine applications, drilling, rigging etc

Below are the most common alloys of monel.

Trade Name ASTM/AISIAlloy type UNS %Copper %Aluminium %Titanim %Ferrous %Mangenese %Silicon %Ni
Monel 400 B 127,B 164 N04400 28-34 2.5 max 2.0 max 63 min
Monel401 N04401 28-34 2.5 max 2.0 max 63 min
Monel404 N04404 28-34 2.5 max 2.0 max 63 min
Monel K-500 B 865 N05500 27-33 2.3-3.15 0.35-0.85 2.0 max 1.5 max 63 min
MonelR-405 B 164 N04405 28-34 2.5 max 2.0 max 0.5 max 63 min

Inconel Fasteners

Inconel Fasteners are nickel alloy fasteners with base of austenitic chromium and nickel also known by the trade name Nickel-Chromium Alloys. It has high corrosion resistance to acids and alkalis with high mechanical properties and ductility subjected to high pressure and heats both.
Inconel fasteners are difficult to machine and hot roll threading is done to ensure 100% thread strength. It forms a passivation oxide layer once heated and hence used at wide range of elevated temperatures.

Applications: Inconel fasteners are used for high-pressure vessels, heat exchangers, nuclear reactors etc.

Hastelloy Fasteners

Hastelloy Fasteners are nickel molybdenum chromium alloy fasteners with base of also known by the trade name Nickel-Chromium-moly Alloys. It has high corrosion resistance to acids and alkalis with high mechanical properties and high resistance to oxidation.
Hastelloy fasteners are difficult to machine and hot roll threading is done to ensure 100% thread strength. It forms a passivation oxide layer once heated and hence used at wide range of elevated temperatures.

Applications: Hastelloy fasteners are used for chemical processing industries, aerospace industries, oil and gas industries etc.