Monel

Solid-solution binary alloy of nickel and copper

You can find more information on our web, so please take a look.

For the DC Comics character Mon-El, see Lar Gand

Monel is a group of alloys of nickel (from 52 to 67%) and copper, with small amounts of iron, manganese, carbon, and silicon. Monel is not a cupronickel alloy because it has less than 60% copper.

Stronger than pure nickel, Monel alloys are resistant to corrosion by many aggressive agents, including rapidly flowing seawater. They can be fabricated readily by hot- and cold-working, machining, and welding.[2]

Monel was created in by Robert Crooks Stanley, who at the time worked at the International Nickel Company (Inco).[3] Monel was named after company president Ambrose Monell, and patented in .[4] One L was dropped, because family names were not allowed as trademarks at that time.[1] The trademark was registered in May ,[5] and the name is now a trademark of Special Metals Corporation.

As an expensive alloy, it tends to be used in applications where it cannot be replaced with cheaper alternatives. For example, in Monel piping was more than three times as expensive as the equivalent piping made from carbon steel.[6]

Properties

[

edit

]

Monel is a solid-solution binary alloy. As nickel and copper are mutually soluble in all proportions, it is a single-phase alloy. Compared to steel, Monel is very difficult to machine as it work-hardens very quickly. It needs to be turned and worked at slow speeds and low feed rates. It is resistant to corrosion and acids, and some alloys can withstand a fire in pure oxygen. It is commonly used in applications with highly corrosive conditions. Small additions of aluminium and titanium form an alloy (K-500) with the same corrosion resistance but with much greater strength due to gamma prime formation on aging. Monel is typically much more expensive than stainless steel.

Monel alloy 400 has a specific gravity of 8.80,[7] a melting range of &#; °C, an electrical conductivity of approximately 34% IACS, and (in the annealed state) a hardness of 65 Rockwell B.[8] Monel alloy 400 is notable for its toughness, which is maintained over a considerable range of temperatures.

Monel alloy 400 has excellent mechanical properties at subzero temperatures. Strength and hardness increase with only slight impairment of ductility or impact resistance. The alloy does not undergo a ductile-to-brittle transition even when cooled to the temperature of liquid hydrogen. This is in marked contrast to many ferrous materials which are brittle at low temperatures despite their increased strength.

Uses

[

edit

]

Aerospace applications

[

edit

]

In the s, Monel metal found bulk uses in aircraft construction, especially in making the frames and skins of experimental rocket planes, such as the North American X-15, to resist the great heat generated by aerodynamic friction during extremely high speed flight. Monel metal retains its strength at very high temperatures, allowing it to maintain its shape at high atmospheric flight speeds, a trade-off against the increased weight of the parts due to Monel's high density.

Monel is used for safety wiring in aircraft maintenance to ensure that fasteners cannot come undone, usually in high-temperature areas; stainless wire is used in other areas for economy. In addition some fasteners used are made from the alloy.

Oil production and refining

[

edit

]

Monel is used in the section of alkylation units in direct contact with concentrated hydrofluoric acid. Monel offers exceptional resistance to hydrofluoric acid in all concentrations up to the boiling point. It is perhaps the most resistant of all commonly used engineering alloys. The alloy is also resistant to many forms of sulfuric and hydrochloric acids under reducing conditions.

Marine applications

[

edit

]

Monel's corrosion resistance makes it ideal in applications such as piping systems, pump shafts, seawater valves, trolling wire, and strainer baskets. Some alloys are completely non-magnetic and are used for anchor cable aboard minesweepers[9] or in housings for magnetic-field measurement equipment. In recreational boating, Monel is used for wire to seize shackles for anchor ropes, for water and fuel tanks, and for underwater applications. It is also used for propeller shafts and for keel bolts. On the popular Hobiecat sailboats, Monel rivets[10] are used where strength is needed but stainless steel cannot be used due to corrosion that would result from stainless steel being in contact with the aluminum mast, boom, and frame of the boat in a saltwater environment.

Because of the problem of electrolytic action in salt water (also known as Galvanic corrosion), in shipbuilding Monel must be carefully insulated from other metals such as steel. The New York Times on August 12, published an article about a 215-foot yacht, "the first ship that has ever been built with an entirely Monel hull," that "went to pieces" in just six weeks and had to be scrapped, "on account of the disintegration of her bottom by electrical action." The yacht's steel skeleton deteriorated due to electrolytic interaction with the Monel.[11]

In seabird research, and bird banding or ringing in particular, Monel has been used to make bird bands or rings for many species, such as albatrosses, that live in a corrosive sea water environment.[12]

Musical instruments

[

edit

]

Monel is used as the material for valve pistons or rotors in some higher-quality musical instruments such as trumpets, tubas and French horns. RotoSound introduced the use of Monel for electric bass strings in , and these strings have been used by numerous artists, including Steve Harris of Iron Maiden, The Who, Sting, John Deacon, John Paul Jones and the late Chris Squire. Monel was in use in the early s by other musical string manufacturers, such as Gibson Guitar Corporation, who continue to offer them for mandolin as the Sam Bush signature set. Also, C.F. Martin & Co. uses Monel for their Martin Retro acoustic guitar strings. The Pyramid string factory (Germany) produces 'Monel classics' electric guitar strings, wound on a round core. In , D'Addario string company released a line of violin strings using a Monel winding on the D and G string.

Other

[

edit

]

Identification tags made from Monel

Good resistance against corrosion by acids and oxygen makes Monel a good material for the chemical industry. Even corrosive fluorides can be handled within Monel apparatus; this was done in an extensive way in the enrichment of uranium in the Oak Ridge Gaseous Diffusion Plant. Here most of the larger-diameter tubing for the uranium hexafluoride was made from Monel.[13] Regulators for reactive cylinder gases like hydrogen chloride form another example, where PTFE is not a suitable option when high delivery pressures are required. These will sometimes include a Monel manifold and taps prior to the regulator that allow the regulator to be flushed with a dry, inert gas after use to further protect the equipment.

In the early 20th century, when steam power was widely used, Monel was advertised as being desirable for use in superheated steam systems.[14] During the world wars, Monel was used for US military dog tags.

Monel doorknobs in the Bryn Athyn Cathedral

Monel is often used for kitchen sinks and in the frames of eyeglasses. It has also been used for firebox stays in fire-tube boilers.

Parts of the Clock of the Long Now, which is intended to run for 10,000 years, are made from Monel because of the corrosion resistance without the use of precious metals.[15]

Monel was used for much of the exposed metal used in the interior of the Bryn Athyn Cathedral in Pennsylvania, religious seat of the General Church of the New Jerusalem. This included large decorative screens, doorknobs, etc.[1] Monel also has been used as roofing material in buildings such as the original Pennsylvania Station in New York City.[1]

The greenish roof of New York's Pennsylvania Station was made from Monel

The &#; Acura (Honda) NSX came with a key made of Monel.[16]

Oilfield applications include using Monel drill collars. Instruments which measure the Earth's magnetic field to obtain a direction are placed in a non-magnetic collar which isolates them from the magnetic pull of drilling tools located above and below the non-magnetic collars. Monel is now rarely used, usually replaced by non-magnetic stainless steels.[17][18]

Monel is also used as a protective binding material on the outside of western style stirrups.

Monel is used by Arrow Fastener Co., Inc. for rustproof T50 staples.

Monel has also been used in Kelvinator refrigerators.

Monel was used in the Baby Alice Thumb Guard, a s-era anti-thumb-sucking device.[19]

Monel is used in motion picture film processing. Monel staple splices are ideal for resisting corrosion from use in continuous-run photochemical tanks.

Monel was latterly widely used to manufacture firebox stays in steam locomotive boilers.

Alloys

[

edit

]

Monel is often traded under the ISO standards (plate, sheet and strip) (bars) (wire) (forgings) and the DIN (pipes and tubes).

Trade Name ASTM/AISI

Alloy type

UNS %Cu %Al %Ti %Fe %Mn %Si %Ni Monel 400 B 127, B 164 N 28&#;34 2.5 max 2.0 max 0.5 max 63 min Monel 401 N 28&#;34 2.5 max 2.0 max 63 min Monel 404 N Rem 0.05 max 0.5 max 0.1 max 0.1 max 52&#;57 Monel K-500 B 865 N 27&#;33 2.3&#;3.15 0.35&#;0.85 2.0 max 1.5 max 0.5 max 63 min Monel 405 B 164 N 28&#;34 2.5 max 2.0 max 0.5 max 63 min

Monel 400

[

edit

]

Monel 400 shows high strength and excellent corrosion resistance in a range of acidic and alkaline environments and is especially suitable for reducing conditions.[20] It also has good ductility and thermal conductivity. Monel 400 typically finds application in marine engineering, chemical and hydrocarbon processing, heat exchangers, valves, and pumps. It is covered by the following standards: BS , NA 13, DTD 204B and ASTM B164.[21]

Large use of Monel 400 is made in alkylation units, namely in the reacting section in contact with concentrated hydrofluoric acid.

Monel 401

[

edit

]

This alloy is designed for use in specialized electric and electronic applications.[22] Alloy 401 is readily autogenously welded by the gas-tungsten-arc process. Resistance welding is a very satisfactory method for joining the material. It also exhibits good brazing characteristics. It is covered by standard UNS N.

Monel 404

[

edit

]

Monel 404 alloy is used primarily in specialized electrical and electronic applications.[23] The composition of Monel 404 is carefully adjusted to provide a very low Curie temperature, low permeability, and good brazing characteristics.

Monel 404 can be welded using common welding techniques and forged but cannot be hot worked. Cold working may be done using standard tooling and soft die materials for better finish. It is covered by standards UNS N and ASTM F96. Monel 404 is used in capsules for transistors and ceramic to metal seals and other things.

Monel 405

[

edit

]

Monel alloy 405, also known as Monel R405, is the free-machining grade of alloy 400.[24] The nickel, carbon, manganese, iron, silicon & copper percent remains the same as alloy 400, but the sulfur is increased from 0.024 max to 0.025-0.060%. Alloy 405 is used chiefly for automatic screw machine stock and is not generally recommended for other applications. The nickel&#;copper sulfides resulting from the sulfur in its composition act as chip breakers, but because of these inclusions the surface finish of the alloy is not as smooth as that of alloy 400. Monel 405 is designated UNS N and is covered by ASME SB-164, ASTM B-164, Federal QQ-N-281, SAE AMS & , Military MIL-N-894, and NACE MR-01-75.

Monel 450

[

edit

]

For more information, please visit Yaoan Wiremesh.

This alloy exhibits good fatigue strength and has relatively high thermal conductivity. It is used for seawater condensers, condenser plates, distiller tubes, evaporator and heat exchanger tubes, and saltwater piping.[25]

Monel K-500

[

edit

]

Monel K-500 combines the excellent corrosion resistance characteristic of Monel alloy 400 with the added advantages of greater strength and hardness.[26][27] The increased properties are obtained by adding aluminum and titanium to the nickel&#;copper base, and by heating under controlled conditions so that submicroscopic particles of Ni3 (Ti, Al) are precipitated throughout the matrix.

The corrosion resistance of Monel alloy K-500 is substantially equivalent to that of alloy 400 except that, when in the age-hardened condition, alloy K-500 has a greater tendency toward stress-corrosion cracking in some environments. Monel alloy K-500 has been found to be resistant to a sour-gas environment.[28] The combination of very low corrosion rates in high-velocity sea water and high strength make alloy K-500 particularly suitable for shafts of centrifugal pumps in marine service. In stagnant or slow-moving sea water, fouling may occur followed by pitting, but this pitting slows down after a fairly rapid initial attack.

Typical applications for alloy K-500 are pump shafts and impellers, doctor blades and scrapers, and oil-well drill collars, instruments, and electronic components. It is also used in components for power plants, such as turbine blades, heat exchangers, and condenser tubes.[29] In marine industry, it is utilized in components for marine hardware, propeller shafts, pump shafts and seawater valves exposed to harsh marine environments.[30]

Monel 502

[

edit

]

Monel 502 is a nickel&#;copper alloy and its UNS no is N. This grade also has good creep and oxidation resistance. Monel 502 can be formed in different shapes, and can be machined similar to austenitic stainless steels.

See also

[

edit

]

References

[

edit

]

Citations

[

edit

]

General and cited references

[

edit

]

• Shoemaker, Lewis E.; Smith, Gaylord D. (September ). "A Century of Monel Metal: &#;". JOM. 58 (9): 22. Bibcode:JOM....58i..22S. doi:10./s-006--x. S2CID .

In the world of advanced engineering and industrial applications, the right materials can make all the difference. Enter Monel wire, a high-performance alloy known for its remarkable properties and versatility. Whether you&#;re a marine engineer searching for materials that can withstand the relentless assault of seawater, an aerospace expert needing components that endure extreme temperatures, or a chemical plant operator looking for robust solutions to handle aggressive substances, Monel wire has something to offer. This article delves into the unique composition and superior characteristics of Monel wire, exploring its diverse applications across various industries. From marine hardware and aerospace components to medical devices and chemical processing equipment, discover how Monel wire&#;s exceptional corrosion resistance, strength, and thermal stability make it an indispensable material in today&#;s most demanding environments. Join us as we uncover the myriad uses and benefits of this extraordinary alloy, and see why Monel wire is a trusted choice for engineers and manufacturers around the globe.

Introduction to Monel Wire

Composition and History

Monel wire is a versatile and durable alloy made mainly of nickel and copper, along with small amounts of iron, manganese, carbon, and silicon. Monel was developed in by Robert Crooks Stanley at the International Nickel Company (INCO). It was named after the company president, Ambrose Monell, and the name was patented in .

Properties

High Strength and Toughness

Monel wire is stronger and tougher than pure nickel, making it ideal for applications requiring durability and resistance to mechanical stress.

Corrosion Resistance

Monel wire resists corrosion from aggressive agents like seawater, acids, and alkalis, making it perfect for harsh environments.

Thermal Stability

Monel wire retains its mechanical properties across a wide temperature range, suitable for high-temperature uses.

Good Ductility

Despite its strength, Monel wire can be easily shaped into wires, sheets, and rods without losing its integrity.

Advantages

Monel wire has several advantages over other materials, making it popular in various industries:

Exceptional Corrosion Resistance

A key advantage of Monel wire is its exceptional corrosion resistance in diverse environments, such as marine and chemical processing.

High Mechanical Strength

Its high strength and toughness make Monel wire suitable for applications involving mechanical stress.

Thermal Stability

Monel wire endures extreme temperatures without losing performance, ideal for high-temperature settings.

Ease of Fabrication

Monel wire&#;s ductility allows easy shaping and fabrication into various forms, aiding its use in multiple applications.

Applications

Thanks to its unique properties, Monel wire is used in many industrial applications:

Marine Engineering

Its seawater corrosion resistance makes it perfect for marine hardware, propeller shafts, and seawater valves.

Aerospace Industry

Monel wire is used in high-performance components that endure extreme conditions, like those in jet engines.

Chemical Processing

It handles corrosive chemicals like sulfuric and hydrofluoric acid, especially in pumps, valves, and heat exchangers.

Medical Industry

Monel wire&#;s biocompatibility makes it suitable for certain medical equipment and implants.

Industrial Applications

Marine Engineering

Monel wire is highly valued in marine engineering for its outstanding resistance to seawater corrosion. This makes Monel wire ideal for various surface and underwater marine applications, including boat and shipbuilding.

Monel wire is often used to make propeller shafts, seawater valves, and pumps. These parts benefit from Monel&#;s strength and corrosion resistance, ensuring the integrity and performance of marine vessels.

Aerospace Industry

The aerospace industry uses Monel wire for its ability to withstand high temperatures and corrosive environments, making it suitable for critical applications. Monel wire is used in aerospace parts that must work under extreme conditions, like jet engines.

Monel wire is used to make aircraft components like fasteners, springs, and safety wiring, which need to withstand mechanical stress and corrosion.

Chemical Processing

Monel wire&#;s resistance to corrosive chemicals makes it popular in the chemical processing industry for various equipment. In chemical plants, Monel wire handles aggressive substances like sulfuric and hydrofluoric acid. Its resistance to harsh environments helps maintain processing equipment integrity.

Monel wire is used in pumps, valves, and heat exchangers, which must resist corrosive chemicals to ensure long-term functionality and reduce maintenance.

Medical Industry

Monel wire&#;s biocompatibility and resistance to bodily fluids make it ideal for medical equipment and implants. Monel wire is used in medical devices and implants because it resists corrosion from bodily fluids. This ensures medical devices are durable and reliable, crucial for patient safety and effective treatments.

Monel wire is used in surgical instruments, dental devices, and orthopedic implants, as its biocompatibility ensures it is safe and effective for medical use.

Specific Use Cases

Electrical and Electronic Applications

Monel wire&#;s unique properties make it ideal for various electrical and electronic applications. Its excellent corrosion resistance and good electrical conductivity are especially valuable for these uses.

Resistance Wires

Monel wire is often used in heating elements due to its ability to withstand high temperatures. This makes it ideal for electric heaters, toasters, and other heating devices.

Thermocouples

Monel wire is used in thermocouples for temperature measurement. Its stability and resistance to oxidation at high temperatures ensure accurate readings in industrial settings.

Conductive Wiring

Monel wire is used in conductive wiring where corrosion resistance is important. This includes harsh environments where traditional copper wires might fail, ensuring reliable performance over time.

Oil and Gas Industry

Monel wire&#;s durability and corrosion resistance make it essential in the oil and gas industry.

Offshore Equipment

Monel wire is used extensively in offshore oil rigs and underwater pipelines. Its resistance to seawater corrosion ensures these components last longer and work reliably, reducing the risk of leaks and failures.

Subsea Installations

Monel wire is used in various subsea installations. Its strength and resistance to stress corrosion cracking are crucial in these demanding environments.

Musical Instruments

Monel wire&#;s durability and unique sound qualities make it a top choice for high-end musical instruments.

Strings for Instruments

Monel wire is commonly used for guitar and violin strings. It resists corrosion from sweat and environmental factors, prolonging string life and maintaining sound quality.

Reed Plates

In wind instruments, Monel wire is used for reed plates because it resists wear and corrosion. This ensures clear and reliable sound production over time.

Seawater Desalination

Monel wire is also used in seawater desalination plants.

Evaporators and Heat Exchangers

In desalination plants, Monel wire is used in evaporators and heat exchangers. Its resistance to seawater corrosion ensures a long service life, making the desalination process more efficient and cost-effective.

Piping Systems

Monel wire is used in the piping systems of desalination plants. It withstands the harsh conditions of seawater exposure and the mechanical stresses of desalination.

Properties and Benefits

Corrosion Resistance

Monel wire is highly valued for its outstanding corrosion resistance, thanks to its high nickel and copper content. This resistance is particularly effective in harsh environments, such as those involving seawater, acidic and alkaline solutions, and other corrosive substances, making it ideal for marine, chemical processing, and oil and gas applications.

High Mechanical Strength

Monel wire offers high tensile strength and toughness, making it capable of withstanding significant mechanical stress and heavy loads. This strength comes from its alloy composition, which includes nickel, copper, and small amounts of iron and manganese. These properties ensure reliable performance in demanding environments like aerospace and industrial machinery.

Thermal Stability

Monel wire maintains its properties even at high temperatures. This is crucial for applications such as jet engines and heat exchangers, where the wire&#;s ability to stay strong and resist deformation under heat enhances its longevity and reliability.

Ease of Fabrication

Monel wire is easy to work with, making it useful for various industrial applications. It can be welded, machined, and formed into different shapes and sizes, allowing manufacturers to create a wide range of components without compromising performance.

Non-Magnetic Properties

Monel wire is non-magnetic, which is beneficial in applications where magnetic interference must be minimized. This property is particularly valuable in electronic and electrical applications, ensuring that it does not interfere with sensitive electronic signals or components.

Cost-Effectiveness

Although Monel wire might be more expensive initially, its durability and corrosion resistance often result in lower long-term costs. Its longevity and reliability reduce the need for frequent replacements and maintenance, making it a cost-effective choice.

Versatility

Monel wire&#;s versatility allows it to be used in many industries and applications. Its unique properties make it suitable for marine hardware, chemical processing equipment, aerospace components, and medical devices.

Biocompatibility

Monel wire is biocompatible and resistant to bodily fluids, making it suitable for medical applications. It is used in medical equipment and implants, where its resistance to bodily fluids ensures the safety and longevity of devices.

Frequently Asked Questions

Below are answers to some frequently asked questions:

What is Monel wire made of?

Monel wire is primarily composed of a blend of nickel and copper, with the typical composition being around 67% nickel and 30% copper. Additionally, it contains small amounts of other elements such as iron, manganese, carbon, and silicon. This specific combination of metals imparts Monel wire with its notable properties of high strength, toughness, corrosion resistance, and thermal stability, making it suitable for various demanding industrial applications.

How does Monel wire compare to stainless steel?

Monel wire, a nickel-copper alloy, is known for its exceptional corrosion resistance, particularly in marine environments and acidic solutions. It maintains high strength and durability over a wide temperature range, making it suitable for demanding applications. In contrast, stainless steel, an alloy of iron and chromium (with varying amounts of nickel and molybdenum), also offers good corrosion resistance and mechanical strength, but its performance can vary significantly depending on the grade and specific environment. While stainless steel is versatile and widely used, it may not match Monel&#;s superior corrosion resistance and high-temperature strength in certain applications. Therefore, the choice between Monel wire and stainless steel depends on specific requirements such as the need for corrosion resistance, strength, and durability in the intended use.

What are the common applications of Monel wire in the marine industry?

Monel wire is commonly used in the marine industry for several critical applications due to its exceptional corrosion resistance, high strength, and durability in harsh seawater environments. It is used to secure ropes and cables in rigging and mooring operations, ensuring reliable performance in marine engineering and shipbuilding. Monel wire is also employed in the construction of propeller shafts, seawater valves, pumps, and other essential components. Additionally, it is utilized in offshore oil and gas operations, underwater equipment, and desalination plants. Marine hardware and fasteners made from Monel wire benefit from its robust properties, making it a preferred material for long-term use in marine conditions.

Can Monel wire be used in high-temperature environments?

Yes, Monel wire can be used in high-temperature environments. Monel 400 wire, in particular, retains its mechanical properties over a wide temperature range, from -300°F (-184°C) to 500°F (260°C). It maintains its strength at elevated temperatures, making it suitable for applications in the aerospace industry, chemical processing plants, and electrical and electronic applications. Its excellent corrosion resistance further supports its use in these high-temperature environments, where both durability and stability are critical.

What makes Monel wire suitable for medical applications?

Monel wire is suitable for medical applications due to its excellent corrosion resistance, biocompatibility, high strength, and non-magnetic properties. Its resistance to corrosion ensures durability and reliability in medical environments exposed to bodily fluids and cleaning agents. The biocompatibility of Monel wire means it does not cause adverse reactions when in contact with biological tissues, making it safe for implants and medical devices. Additionally, Monel wire maintains its strength and mechanical properties even at high temperatures, which is essential for equipment subjected to sterilization processes. Its non-magnetic nature is also beneficial in environments where magnetic interference could be problematic, such as in MRI machines. These combined properties make Monel wire an ideal material for various medical applications.

How does Monel wire resist corrosion in chemical processing plants?

Monel wire resists corrosion in chemical processing plants primarily due to its unique nickel-copper composition. Monel 400, for example, contains about 67% nickel and 30% copper, along with small amounts of iron and manganese. This combination provides excellent resistance to a wide range of corrosive environments, including acids, alkaline solutions, and seawater. The alloy is particularly effective against hydrochloric and hydrofluoric acids when de-aerated and can withstand sulfuric acid at moderate temperatures and concentrations. Additionally, Monel wire maintains its mechanical properties under high temperatures and fluctuating conditions, making it ideal for use in pumps, valves, heat exchangers, and other equipment exposed to harsh chemicals. This exceptional corrosion resistance, coupled with high strength and thermal stability, makes Monel wire a preferred material in chemical processing plants.

If you want to learn more, please visit our website monel wire mesh.