Magnets are interesting fun things. We have magnets in our daily course of life from Toys to heavy industry (magnet application) which require a
“The strong permanent magnets made from alloys of rare earth elements are termed as Rare Earth Magnets”.
The ultimate difference between Rare earth magnets and other permanent magnets is that rare earth magnets are made from alloys of rare earth elements while other permanent magnets are ferrite or alnico(magnet application). Generally, rare earth elements are called so because of two significant reasons. The first naming reason relies on the initially perceived dearth of all rare earth elements. The second one emerges from the fact that it is quite difficult for each rare earth element to extract it purely from its mineral ore bed.
The magnetic field typically produced by
To understand rare earth magnets completely, it is important to know what they are made of and where they come from. In the Rare earth class of the periodic table, 15 elements are called lanthanides, and
Rare earth magnets are considered second-generation magnets with their deviates expanding to 4th Generation. Manufacturing of these magnets was initiated in the late twenty century i.e. 1970. The first Rare earth magnet developed was YCo5 by Strnat of the U.S Air force
There are many processes for manufacturing rare earth magnets. The most common method is known as Powder Metallurgy. In the conventional powder metallurgy manufacturing route, the casting of the alloy is carried out, Crushing and grinding to achieve single domain particle size is obtained either by Jet Mill or Ball Mill. The third step is to press the sample in a magnetic field to align particles in the easy axis of magnetization. After CIP, samples are sintered for achieving high density and high coercivity.. Ferrite, Samarium Cobalt (SmCo), and neodymium-iron-boron (neo) magnets, all of them are made from powder metallurgy methods.
Common applications of Rare Earth Magnets
Since the prices of regular permanent magnets became competitive in the 1990s, neodymium magnets replaced ferrite and alnico magnets in many applications of the industry and many of myriad applications in modern technology, requiring powerful magnets. Common applications of rare earth magnets are:
- Used for head actuators in computer hard drive disks.
- Used in high-performance AC servo motors.
- Useful in wind turbine generators.
- Used in bicycle dynamos.
- Used in loudspeakers and headphones.
- Used to erase heads for cheap cassette recorders.
- Used in fishing reel brakes.
- Used in automatic door locks.
- Magnetic bearings and couplings.
- Used in
bench topNMR spectrometers
- Used in mechanical switches for e-cigarette firing.
- Used in motors having permanent magnets in cordless tools.
- Used in traction motors and integral started generators, both in hybrid and electric vehicles.
- Used in industrialization; for instance maintaining product purity, protection of equipment and quality control.
- Producing mechanically powdered flashlights, electricity generation in shaking or rotating motion (hand
- Used in capturing fine metallic particles in lubricating oils (
crank casesof internal combustion engines), keeping set particles out of circulation, hence rendering them unable to cause grinding wear of moving machine parts.
- Uses in electric machines (motors) such as:
- Cordless tools
- Servo motors
- Lifting and compressor motors
- Synchronous motors
- Spindle and stepper motors
- Electrical power steering
- Uses in electric generators for wind turbines (only generators having permanent magnet excitation).
- Used in turbines that
utilizesgears requiring less paramagnetic material per megawatt.
- Used in retail media case decouplers.
- Used in industrial processing where powerful neodymium magnets are required to catch foreign bodies and to protect product and processing.