Monel Fasteners

Monel fasteners are nickel-copper based alloys that are machined to provide excellent corrosion resistance and a silver-white finish.

Nickel Alloy Fasteners include Monel bolts, Monel screws, Monel nuts, and various other customized types of fasteners.

High Nickel alloys are available in a variety of grades, such as Monel 400 and Monel K500, which are commonly used for fasteners.

Monel 400 Fasteners

Monel 400 Fasteners are mainly used as fasteners for chemical equipment, heat exchangers, boiler feedwater heaters and petrochemical pipelines, as well as in offshore applications.

Due to the high nickel content in Monel 400 (UNS N04400 or MCu-28-1.5-1.8 or Ni68Cu28Fe), it is one of the most widely used and versatile alloys with excellent overall performance.

This alloy has excellent corrosion resistance in hydrofluoric acid and fluorine gas media, and also has excellent corrosion resistance to hot concentrated lye.

It is also resistant to corrosion from neutral solutions, water, seawater, atmosphere, organic compounds, and so on. An important feature of this alloy is that it generally does not produce stress corrosion cracks and has good cutting properties.

Monel K500 Fasteners

K500 Monel Fasteners are parts of fastening systems used in petroleum equipment, chemical shipbuilding industry, pharmaceutical industry.

In addition to its excellent mechanical properties such as high strength, corrosion resistance and non-magnetic properties, Monel K500 has the same corrosion resistance as Monel 400. Since the alloy has no plastic-brittle transition temperature, it is very suitable for a variety of low-temperature equipment

Material Monel K500 has the same corrosion resistance as Monel 400 but with higher mechanical strength and hardness.

Monel Bolts

monel 400 hex screws
monel 400 hex bolts

Monel Nuts

monel nuts
monel 400 nuts

Monel Screws

monel k500 bolts and nuts
monel screws

Monel Bolts and Nuts Supplier

Ding Fastener China is a leading monel fasteners manufacturer, all raw materials are purchased from large-scale steel mills, which can guarantee the chemical composition is 100% qualified.

Our main production of Monel fasteners includes hexagon head bolts (full or half tooth), hexagon socket head cap screws, machine screws and wood threaded screws of various drive head types, and hexagon nuts to match with the bolts and screws.

monel fasteners

Monel Fasteners Supplier

Monel 400 Chemical Composition

monel 400 Chemical Composition

Monel 400 Physical Properties

monel 400 physical properties

Monel 400 Mechanical Property

monel 400 mechanical property

Monel K500 Chemical Composition

monel K500 chemical composition

Monel K500 Physical Properties

monel k500 physical properties

Monel K500 Mechanical Property

monel K500 mechanical property

Corrosive Properties of Monel

Seawater Environment

The corrosion rate of monel in static seawater is 0.00mm/a. The corrosion rate of high silicon monel alloy under different flow rates is less than 0.020 mm/a, and the values are similar, which is very suitable for use in flowing seawater.

It is resistant to both static seawater and high-speed flowing seawater corrosion, and can be used for corrosive parts in a variety of marine environments, including ships, aircraft carriers, wharves, drilling platforms, shallow oilfields, cross-sea bridges, submarine pipelines and so on.

Hydrofluoric Acid

Monel is resistant to corrosion in all concentrations and at all temperatures of hydrofluoric acid. When hydrofluoric acid contains oxygen and oxidizing salts, it increases the corrosion rate of Monel, so the equipment should be isolated from air when operating.

Monel is less affected by the flow rate, so pumps, valves, blisters and other equipment and parts in conditions of high flow rate are more appropriate to use monel. In various concentrations of hydrofluoric acid, monel has good corrosion resistance up to 120℃.

The corrosion rate of high-silicon monel in some hydrofluoric acid is less than that of ordinary monel, see the following table.


In NaOH at concentrations less than 75% and temperatures less than 135°C, the corrosion rate of Monel is less than 0.01 mm/a, and at lower concentrations and lower temperatures, the corrosion rate is often less than 0.0025 mm/a.

General characteristics: The corrosion of caustic soda increases with increasing temperature. Monel alloys can be applied to caustic soda at high temperatures and concentrations.

The corrosion behavior in KOH is essentially similar to that in NaOH. In NH4OH solution, the corrosion resistance of monel is better than pure nickel, but it is only allowed to be used in concentrations below 3%.

Sulfuric Acid

Monel in reducing sulfuric acid medium, the corrosion rate is very low, in the 30 ℃ sulfuric acid without air, Monel in the concentration of less than 85% of the sulfuric acid are corrosion-resistant.

Concentration higher than 85%, due to the sulfuric acid is oxidizing, strong oxidizing sulfuric acid to make its corrosion rate increased dramatically.

However, the corrosion resistance of high silica monel in low and medium temperatures, for various concentrations of sulfuric acid, has increased to a greater extent, because the alloying element silicon improves the corrosion resistance of the alloy.

In dilute sulfite media, Monel has very good corrosion resistance and can therefore be used as a structural material in a number of applications in the paper industry.

High Temperature Corrosion

Tests in air and oxygen show that the oxidation resistance of monel is quite good, but lower than that of pure nickel.

At this point, the outer layer of the surface of the Monel alloy contains CuO and Cu2O, while the inner layer is rich in Ni and essentially pure NiO.

The maximum temperature at which Monel alloys can be operated continuously in air is generally about 600°C. The maximum temperature at which Monel alloys can be operated continuously in air is usually about 600°C.

In high-temperature vapors (both dry and wet vapors), Monel can be used at temperatures less than 485°C. In high flow rate vapors, Monel is also very resistant to impulse corrosion.

Stressed monel alloys can be used at temperatures up to 455°C, above which intergranular corrosion occurs, especially between 470 and 500°C. The corrosion rate of monel alloys is less than 0.026 mm/a in 150-250°C dry vapor, tested for 1000-1150 hours.

Monel Wear Resistance

The samples are high silica monel in aging state, hardness HRC42, in kerosene against Cr18, the friction coefficient is 0.06, and the wear resistance is 0.8mg for 8 hours of wear at a unit load of 0.5MPa and speed of 2.5m/s. The samples are in aging state of high silica monel, hardness HRC42;

In kerosene against aluminum brass, the friction coefficient is 0.035, and the wear resistance is 0.7mg for 3 hours of wear at a unit load of 3.5MPa and a speed of 0.5m/s .

Contact the Experts

Blank Form (#3)