Magnets are metallic composites, usually ferrous metal composites, which
produce a “magnetic field”; the magnetic field causes other magnetic
objects to be attracted to the magnet while other magnets are either
attracted or repelled. There are many different types of magnets all
with different magnetic strength, heat resistance, corrosion tolerance
Magnets can largely be broken up into two categories: non-permanent and permanent; non-permanent magnets are electromagnets which require an external source of power and are triggered electrically to be magnetic. Electromagnets have many industrial applications such as solenoid valves, AC and DC motors, biomagnetic separation, transformers and so on. Permanent magnets include ceramic magnets (also known as ferrite magnets), alnico magnets and rare earth magnets. For instance, ceramic magnets have lower magnetic power and are more brittle and easily breakable than some other magnets, but they are much more cost-effective and are used in non-structural applications in motors, magnetic chucks and magnetic tools. Rare earth magnets, on the other hand, are less cost-effective to manufacture but are far more powerful and retain their magnetism better than ferrite magnets; they are used as industrial magnets for holding and lifting, motors, speakers and sensors, testing and MRIs.
Magnetic assemblies are tools or systems which use electromagnets, ceramic magnets, alnico magnets, rare earth magnets or a combination to do specific kinds of lifting, holding or separating of metallic materials. Combinations of different magnets in assemblies can increase the overall magnetic force of the tool. Most magnetic assemblies used in industrial and metal manufacturing use permanent industrial magnets to do various kinds of physical work, including metal parts and sheet metal lifting, mounting and holding, separating and water treatment. Permanent and nonpermanent (electromagnetic) magnet assemblies are used in automotive, aerospace, electronics and biomedical fields in beam control, film and software disk programming and erasing, Magnetic Resonance Imaging (MRI), sound speakers, sensors, TV monitors, welding equipment, power meters, ignition timing systems, linear actuators, blood testing and separating, electric motor activation and more. Many types of magnets are specifically used for certain industries and applications. For example, sheet magnets are a flexible ferrite-plastic composite which is extruded into magnetic sheets and used in automotive and consumer industries, and can be cut into magnetic strips of rubber material. Bar magnets are the most common type of magnet used today, and are made from a ferrite metal material.
The most important properties magnet manufacturers consider during fabrication are porosity, ease of fabrication, magnetic retention under heat and corrosion, magnetic strength and cost. There is not one magical type of magnet that will have all of these characteristics, and different types of permanent magnets are made from various composites and therefore have very different properties and applications. Ceramic magnets are sintered powder composites of ceramic powder, iron oxide and either strontium or barium. Ceramic magnets can be compressed, extruded or sintered into a variety of shapes. The finished material is a cost-efficient, brittle, porous charcoal gray ceramic which is often sintered into arcs for motors, discs and blocks for lifting and holding. In addition, because ceramic magnets are porous they are highly susceptible to corrosion and lose their magnetism under high temperatures. Slightly more expensive alnico magnets are composites of aluminum, nickel, cobalt and iron and are similar to ferrite ceramic magnets but are less brittle, more easily fabricated into shapes, and have higher magnetic resistance.
Rare earth magnets include neodymium magnets and samarium cobalt magnets and are far more powerful than ferrite ceramics or alnico magnets. Rare earth lanthanide elements neodymium and samarium have partially filled outer f-electron shells which are the source of their exceptionally powerful magnetic fields. Neodymium magnets are neodymium, iron and boron composites with more powerful magnetic pull than any other type of magnet. Although they have high magnetic force, neodymium magnets have low heat and corrosion resistance and lose magnetism under 200 degrees Celsius or more. Samarium cobalt magnets are composed of samarium and cobalt and are much more resistant to demagnetization and corrosion than neodymium magnets, with a thermal stability of up to 550 degrees Celsius. Samarium cobalt is therefore used most in high heat applications such as motors and medical tools. Neodymium magnets are harder than ceramic magnets but are still brittle and are therefore most often nickel-coated for protection. Due to the scarcity of rare earth materials and the long process of rare earth extraction from lanthanide ores, rare earth magnets are significantly more costly than non rare earth magnets.
Magnet Manufacturers – Alliance, LLC
Magnet Suppliers – International Magnaproducts, Inc.
Magnet Suppliers – International Magnaproducts, Inc.
Magnet Manufacturers – Master Magnetics, Inc./The Magnet Source™
Sheet Magnet Manufacturing – Master Magnetics, Inc./The Magnet Source™
Magnet Suppliers – International Magnaproducts, Inc.
Applications of Industrial Magnets
Due to their wholly unique properties, industrial magnets show up in nearly every modern industry. There's no adequate replacement for the basic properties of magnets in many cases—and those unique properties can frequently be used in unusual ways to amazing end results. Notable applications include:
- Sorting- A simple application of basic magnetic properties allows one to sort ferrous materials from non-ferrous materials, and magnetic materials from non-magnetic materials.
- Magnetic Sweepers- Another rudimentary application, which uses magnets to attract loose ferrous components for safety and loss prevention.
- Imaging Devices- Advanced application for medicine and other fields, producing images of otherwise unviewable places and things.
- Lifts- Industrial application using magnets in magnetic pick-up to lift, hold, and move ferrous materials with less moving components.
- Data Storage- Credit cards, hard drives, and other data storage mediums depend on magnetism to function.
- Household Goods- Refrigerator magnets, basic holds for cabinets and doors, and similar household applications.
- Maglev Trains- Use of repelling magnets to allow for low-friction movement of trains over magnetic rails at high speeds.
- Seals- Used to securely close refrigerators and other containers.
- Generators and Electric Motor- A key component in any electric motor or motor assembly, though the type of magnet may vary.
- Electronics- Many electronic devices use magnets for various proprietary purposes, such as the deflection of electrons in a cathode ray tube television.
History of Magnets
Natural magnets have been used for much of recorded history, dating back to ancient Chinese mariners who utilized the properties of natural magnetite for compasses. The earliest attempt to scientifically research magnetism in general came much more recently, however, with the experiments of William Gilbert in 1600. During his research he also discovered the earliest ways to produce magnets and the influence of temperature on magnetism.
Heavy industrial use of magnets came much later, after additional breakthroughs in electronics and magnetism by famous physicists such as J.J. Thomson. While rudimentary electromagnetic generators and other magnet-dependent technologies existed at the turn of the 19th century, only in the 20th century did our understanding of magnetism and its properties advance enough for many of our most advanced modern applications.
Rare-earth magnets, some of the most potent industrial magnets, weren't developed until as recently as the 1970s and 1980s, while superconducting magnets were theorized in 1911 but only successfully made in 1955. Smaller advances and breakthroughs have accelerated through recent years alongside the general development of superconductors and electronics.
Design and Engineering for Magnets
There are a few general components of magnet design you'll want to have in mind when talking to a supplier.
First, you'll want to know either the specific type of magnet you'll need, or the details of strength/durability/permanence/etc. so your supplier can make a recommendation.
You also need to know the shape your magnet should be for your application. If the shape doesn't matter, you can save money by accepting whatever is easiest to produce; conversely, complex designs will run more.
Coating for magnets requiring additional protection against wear and tear or chemical corrosion should also be considered, as some magnets may not be suitable for certain coatings.
Environment will also play an important rule, as many magnets function very differently under different temperatures, while others may have component metals such as iron rust in moist environments without additional treatments or coatings.
Most industrial magnets can be cleanly sorted into one of four major categories:
- Permanent Magnet- Permanent magnets are the most commonly used magnets, and maintain permanent magnetism.
- Temporary- Materials which operate as magnets in the presence of strong magnetic fields, usually simple ferrous materials. Used in various electronic devices.
- Electromagnets- These magnets work by virtue of the magnetic fields produced by electric current. These work with a continuous supply of electricity through a tightly wound custom coil of wire, and can be turned off or on at will. Used in many electronic devices.
- Superconductors- Are similar to electromagnets, but must be cooled below a certain temperature and feature no metal core. The strongest type of magnet, used for heavy industrial magnetic separator machines, MRI machines, and other magnetically intense processes.
While magnets may all fall into more basic categories, there are many other descriptors used to identify the type, purpose, or materials of a magnet.
- Alnico Magnet- Magnets produced from a mixture of cobalt, nickel, and aluminum, with high permanence and strength compared to the majority of magnets; alnico magnet is only exceeded by rare earth magnets.
- Ceramic Magnet- Any magnet made of iron oxide with strontium carbonate or other ceramic magnet materials.
- Neodymium Magnets- AKA neodymium iron boron magnets. Magnets made from a combination of boron, iron, and neodymium.
- Rare Earth Magnets- Magnets made up of various Rare Earth elements. Very powerful.
- Ferrite Magnet- Common lost-cost magnets, magnet ferrite is usually brittle but otherwise resilient. Another name for a ceramic magnet.
- NdFeB Magnet- Another term referring to neodymium magnets; Neodymium, Iron, Boron.
- SmCo Magnet- Samarium cobalt magnets, a type of permanent magnet made up of rare earth metals samarium cobalt. Application/form.
- Bar- Any of a number of ferromagnetic materials or composites made in the shape of a narrow rectangle.
- Bipolar Assemblies- Special heat resistant magnetic magnetic assembly with a wide reach, useful for alignments, holding applications, and similar tasks.
- Strips- Thin pieces of magnetic material, usually magnetic rubbers with adhesives for attaching to irregular surfaces.
- Assemblies- Systems and tools composed of magnets and other components, designed usually for lifting, separation, or holding of magnetic or metal materials.
- Sheet Magnets- Describes and large, flat magnet used for covering large areas.
Custom. Any magnet made of any material to set specifications for a given application.
Advantages and Benefits
Many industrial magnets see use in highly specific products, so it's difficult to state the advantages of such magnets; a classic CRT monitor or television only works because of industrial magnets, but of course there's no alternative for that exact technology. The same holds true for many products where magnets serve as key components due to their wholly unique properties.
General industrial use, however, offers a number of consistent benefits to the companies using magnets.
Reduce Maintenance Costs
There are a variety of ways magnets can reduce maintenance costs. Collecting ferrous materials can prevent punctured tires, damage to mechanical components, even injury of personnel. Clever use of magnets in various industrial machines can also reduce mechanical wear and tear by reducing the need for moving parts in holding and lifting mechanisms.
Many manufacturers use general purpose magnets to attract ferrous and magnetic materials on production lines and in storage scenarios. This can be particularly important in food, medicine, and chemical production industries.
Quick Sorting and Separation
The simplest application of magnets lay in the ease with which they can sort ferrous from non-ferrous, magnetic from non-magnetic. If you have any sorting application involving this type of material, it can save many hours of work and headache.
Most industrial magnets serve as components in larger devices or assemblies, so there's not much need for accessories for the individual magnets. Smaller magnets used raw, however, can benefit from a few added pieces of technology.
- Covers- Various covers serve to protect magnets from physical damage, insulate nearby electronics from them while out of use, or prevent demagnetization.
- Ferrous Components- Small ferrous components, such as steel-and-nickel discs, can be used in combination with magnets for any number of purposes.
- Connectors and Adhesives- Connecting magnets to other materials sometimes involves the use of special connectors and adhesives.
Use and Installation
It's difficult to give a single explanation for the use and installation of magnets, due to the wide range of applications for industrial magnets. Despite the variation in the specifics, however, there is one area where universal rules hold true: Safety…
- Goggles- There are several reasons to wear goggles when handling heavy duty magnets. They can shatter, or break other materials. When used in machining or other industrial tasks, they can burn or spark dangerously.
- Gloves- Heavy duty magnets can cause abrasions, sprains, and broken bones if handled improperly. Magnets can also shatter and cut the skin. Heavy duty gloves are advised.
- Electronics- Be careful with any industrial magnet near electronic devices or data storage, as the magnetic fields can interfere with the function of such devices and damage or destroy them.
- Pacemakers- As a form of electronic device, pacemakers are susceptible to interference from industrial magnets. This can prove lethal, so anyone with a pacemaker or other medical device susceptible to magnets should avoid work with industrial magnets without doctor approval.
- Allergies- Many individuals suffer from allergies to the component metals of common industrial magnets, so it's important to stay alert to inhalation, dust, contact for such people.
- Navigation- Certain strong magnets can interfere with navigation tools such as GPS, so special precautions must be taken when traveling with industrial magnets.
- Transport- When shipping powerful magnets alone or as components, it's important to make sure they will not interfere with transportation or adhere to surfaces through the shipping container.
Inspection rules for magnets will depend on the application at hand. While all magnets function best when cleaned and decontaminated regularly, the degree of degradation and the necessary frequency of cleaning will need to be determined with use.
Regular testing of any magnet regularly holding loads should also be performed, to avoid unexpected failures of magnetism and the drop of heavy ferrous materials. If you're not sure whether a magnet is working properly or not, you can contact your manufacturer for testing or replacement.
Compliance and Standards
Compliance and standards are application-specific with industrial magnets, given the wide variety of applications. Carefully researching the standards of magnets for your application will make the manufacturing process for custom magnets much easier. If you're unsure of standards or compliance requirements for your application, your manufacturer may be able to help you.
Of course, general safety concerns apply to all uses of magnets, especially powerful rare earth magnets, superconductors, and electromagnets.
Choosing a Manufacturer
Because of the many differences in industrial magnet applications, it can be difficult to identify a single 'best' manufacturer in your area. Instead, you should look for a manufacturer best suited to your needs and expectations as a customer. Look for these traits:
- Familiarity with Your Specific Need-First and foremost, you want an industrial magnet supplier familiar with the type of magnet you're using. Ideally, one familiar with your exact use scenario or something very similar. References from similar businesses and applications should be a high priority here. A supplier familiar with your needs and expectations can offer superior service, lower expenses, and fewer mistakes.
- Versatility- You want a manufacturer that can customize to your exact needs. That doesn't mean a manufacturer with a one-size-fits all solution close to what you need. The best custom magnet fabricators will go the extra step to meet your needs—and adjust as necessary to any unusual requests.
- Transparency- You want to fully understand what you're getting for what you pay in every interaction with a vendor, supplier, or contractor. This holds true with magnets as it does with anything else.
- Schedule- Make sure you're working with magnet manufacturers or suppliers that can meet your scheduling needs. You don't want to end up deep in a project only to find out you won't have the magnets necessary to proceed for weeks or months to come.
- Alnico magnets are sintered from a compound of aluminum, nickel
and cobalt and have higher magnetic permanence and strength than all other
non-rare earth magnets.
- Bar magnets are narrow, rectangular pieces of ferromagnetic material or composite that generate a magnetic field.
are advantageous during part transference, welding alignments and part
holding applications. Bipolar magnetic assemblies maintain high heat
resistance and wide magnetic reach.
maintain resistance to demagnetization, can withstand exposure to electrical
fields and vibration and are economical. Their demagnetization resistance
is beneficial in the welding and construction industries, as well as
other environments subject to vibration and electricity, but they do
have low heat resistance.
- made of strontium carbonate and iron oxide.
- Custom magnets are sheet, alnico, neodymium, rare earth or ceramic magnets which
are fabricated to specialized sizes, magnetic strengths or densities to fit
require an electric current for the production of a magnetic field.
- Industrial magnets are heavy-duty magnets used for industrial applications.
- Magnetic assemblies are tools and systems that use large amounts of magnets to lift, separate and hold metallic materials.
- Magnetic strips are thin pieces of flexible magnetic rubber material that usually have
an adhesive on one side and can conform to irregular or uneven surfaces.
- Neodymium magnets are composed of a combination of neodymium, iron, and boron.
- Permanent magnets retain magnetism without a magnetic field. Permanent magnets do not
generate electricity or heat.
maintain the highest holding ability of all magnetic assemblies in a
compact design but generally possess low heat resistance. Rare earth
magnets consist of neodymium magnets and samarium cobalt magnets, referred
to as rare earth magnets because of their location in the periodic table.
- Rare earth magnets are composed of elements found in the "Rare Earth" part of the Periodic Table.
- Sheet magnets are large, flat magnets that can cover a large area.
- A shorthand reference to magnets made from an aluminum nickel cobalt compound;
these types of magnets have medium to high magnetic strength and have excellent
magnetic resistance to heat.
- Magnetic characteristic whereby magnetic orientation
exists toward a specific direction as a result of the application of
a magnetic field to the magnet during production.
- Encased magnet used to hold identification badges
to clothing without causing damage.
- An electromagnet design in which the magnetic
coil is located between two steel plates parallel to each other, which
act as the north and south poles.
- Magnet assemblies composed of strontium carbonate and iron
oxide that are charcoal in color and typically appear in the forms of
discs, rings, blocks, cylinders and even arcs for motors.
- The temperature at which point the magnetic
properties of a magnet begin to decrease upon exposure.
- A device that can eliminate magnetism in
magnetic assemblies by
using an alternating electrical current.
like temperature, shock, vibration or electrical or magnetic currents
that completely or partially demagnetize magnetic material.
- A commonly used, low-cost magnet that is very
brittle though relatively hard and has good resistance to demagnetization,
good temperature stability and excellent corrosion resistance.
- A material containing iron, making it inherently
- A magnet made by combining
a mixture of ferrite powder and rubber polymer resin, forming it by extrusion
then magnetizing and laminating it with vinyl or adhesive. Flexible magnets
are the most pliable permanent magnet and are the least expensive by
- The measure of strength of the total size
of a given magnetic field found in magnetic assemblies.
- Unit of measurement indicating
- A magnet that is optimal
for any big projects in which large metal products without brackets need
to be lifted. Industrial
magnets are adaptable enough to give companies the flexibility to customize
them in order to make them better and more efficient for specific applications.
characteristic whereby magnetic orientation toward a specific direction
does not exist. Isotropic, or non-oriented,
magnets can be magnetized in all directions.
- A magnet that is part of a lifting device used
to move a variety of ferrous metals, ranging from small bundles of rod
or scrap to large, heavy blocks.
- An area characterized by the movement of an electric
charge. Magnetic fields remain most intense at opposite ends of magnets,
known as the North and South poles.
- The strength of the magnetic field of a magnet
exemplified by the rate of movement of magnetic energy.
- The initial magnetization of an object created
by forces emanating from a magnetic field.
- The direction toward which a magnet is predisposed
as a result of exposure to a magnetic field during production.
- Area of magnetic flux concentration where magnetic
fields are strongest. The North and South Poles are magnetic poles.
- Devices that remove ferrous metals from various
materials, while protecting machinery.
- Unit of measurement indicating magnetic flux.
- A magnet made of a rare earth element that is
smaller, stronger and cheaper than most other magnets.
- Unit of measurement indicating the strength of a
- A magnet that after having been removed from
a magnetic field still retains its magnetism.
- A device that picks up all metal debris
when rolled over spills. A release lever drops everything the rotary
magnetic sweeper picks up, eliminating the need to handle potentially
hazardous metal pieces.