Differenc Between Rare-earth Magnets and Ferrite Magnets
Magnets are objects that generate magnetic fields. These magnetic fields allow the magnet to attract certain metals from a distance without touching the metal. Some magnets are produced naturally, and some are man-made. Although there are many different types of magnets, the two most popular artificial magnets are ferrite magnets and neodymium magnets.
Rare-earth magnets and ferrite magnets are both types of permanent magnets; they are both made of a material that, once it has a magnetic charge, will retain its magnetism for many years unless it is damaged. However, not all permanent magnets are the same. The strength and resilience of rare earth and ferrite magnets are different because they are made of different metal alloys.
For many years, all magnets have been natural magnets, such as lodestone, which is a kind of iron ore with magnetism. In 1952, the magnet was made of ferrite for the first time. By using ferrite to make magnets, engineers can make magnets into any shape they want. By making a carefully manufactured mixture into a ferrite magnet, a magnetic field stronger than that in nature can be generated. Ferrite magnets are cheaper, more powerful, and quickly become popular. Ferrite magnets are also called hard ferrite magnets or ferrite magnets. They are made of strontium or barium ferrite.
There are two types of rare earth magnets: cobalt-samarium magnets (SmCo) and neodymium iron boron magnets (NdFeB). SmCo and neodymium iron boron magnets are called "rare earths" because they are composed of rare earth (lanthanide) elements in the periodic table.
SmCo magnets were developed in the 1970s and were the first rare earth magnets produced. Neodymium iron boron magnets went on the market in 1984.
The relative strength of ferrite and rare earth magnet
The strength of the magnetic field generated by the magnet is quantified by BHmax or maximum energy product, and BHmax or maximum energy product is measured by Megagauss Oersteds (MGOe). The higher the BHmax, the greater the strength of the magnet. Ferrite magnets have a BHmax of 3.5, SmCo has a BHmax of 26, and NdFeB is the most powerful rare earth magnet with a BHmax of 40.
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The relative resistance of ferrite to the thermal stress of rare earth magnet
The magnet will start to lose strength after being heated to a certain temperature (ie Tmax), so it should not be operated outside this temperature. However, when cooled below Tmax, they will regain power. The Tmax of the ferrite magnet is 300 degrees Celsius, the Tmax of the SmCo magnet is 300 degrees Celsius, and the Tmax of the neodymium iron boron magnet is 150 degrees Celsius. If the magnet is heated to a temperature far above Tmax, it will eventually be demagnetized at a temperature called Tcurie. When the magnet is heated to a place outside of Turri, it cannot be recovered once it has cooled down. The t Curie value of a ferrite magnet is 460 degrees Celsius, the t Curie value of SmCo is 750 degrees Celsius, and the t Curie value of NdFeB is 310 degrees Celsius.
Relative durability of ferrite and rare earth magnets
In addition to resisting thermal stress, magnets can also resist other stresses. NdFeB magnets are fragile and difficult to process. They are also prone to corrosion. SmCo magnets are slightly less brittle and difficult to process, but have high corrosion resistance. SmCo magnets are also the most expensive type of magnets. Ferrite magnets are lower in cost than SmCo and NdFeB magnets, and have good demagnetization and corrosion resistance.
Ferrite and neodymium magnets each have different benefits. Ferrite magnets are easy to magnetize. They are very corrosion resistant and generally do not require additional coatings for corrosion protection. They can resist the degaussing of the external magnetic field. They are stronger than natural magnets, although many other types of magnets are stronger than them. They are relatively cheap. Neodymium magnets are the most powerful of all permanent magnets. A neodymium magnet can lift more things than any other type of magnet of the same size. They are extremely resistant to demagnetization by external magnetic fields.
Ferrite and neodymium magnets also have different disadvantages. Ferrite magnets are very fragile and break easily. They cannot be used on machinery that is subject to a lot of pressure or bending. If exposed to high temperatures (over 480 degrees Fahrenheit), they will be demagnetized. They only have a medium-strength magnetic field and are not suitable for applications that require a strong magnetic field. Neodymium magnets are relatively more expensive than ferrite magnets. They are prone to rust and additional measures must be taken to protect them from corrosion. Neodymium magnets are also very fragile and will break under pressure. If exposed to above 175 to 480 degrees Fahrenheit (depending on the alloy used), they will lose their magnetism.
Sheensen Magnetics Technology produce various types of magnet products, including rare earth magnets and ferrite magnets. You can send e-mail to [email protected] to get more magnetic solutions for your product.