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Difference Between Rare Earth Magnets And Ferrite Magnets

Nov. 05, 2019

Magnets are objects that generate magnetic fields that enable them to attract certain metals from a distance without touching them. Some magnets are produced naturally and some are artificial. Although there are many different types of magnets, the two most popular artificial magnets are ferrite magnets and rare earth neodymium magnets. Today Segment Neodymium Magnet Manufacturer will tell you some differences between the two.

Rare earth magnets and ferrite magnets are both types of permanent magnets. They are made of a material that once held with a magnetic charge, it will remain magnetic for many years unless it is damaged. However, not all permanent magnets are the same. Rare earth and ferrite magnets differ in strength and resilience because they are made of different metal alloys.

Ferrite Magnet:

For many years, all magnets were natural magnets, such as lodestone, which is a magnetic iron ore. In 1952, the magnet was first made of ferrite. By making magnets from ferrite, engineers can shape the magnets into any shape they want. By making a carefully manufactured mixture into a ferrite magnet, a stronger magnetic field can be generated than in nature. Ferrite magnets are cheaper, more powerful, and quickly became popular. Ferrite magnets are also called hard ferrite magnets or ferromagnets. They are made of strontium or barium ferrite.

Rare earth magnet:

There are two types of rare earth magnets: cobalt-rhenium magnets (SmCo) and neodymium-iron-boron magnets (NdFeB). SmCo and NdFeB magnets are called "rare earths" because they are composed of rare earth (lanthanide) elements in the periodic table of the elements. SmCo magnets were developed in the 1970s and were the first rare earth magnets produced. NdFeB magnets came on the market in 1984. The most common one is the Internal Threaded Pot Magnet of NdFeB.

Internal Threaded Pot Magnet of NdFeB

Internal Threaded Pot Magnet of NdFeB

1.The relative strength of ferrite and rare earth magnets

The magnetic field strength generated by a magnet is quantified by BHmax or the maximum energy product, and BHmax or the maximum energy product is measured by Megagoss Oersted (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.

2. Relative resistance of ferrite to thermal stress of rare earth magnets

Magnets begin to lose strength when heated to a certain temperature (ie, Tmax), so they 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 NdFeB magnet is 150 degrees Celsius. If the magnet is heated far above Tmax, it will eventually be demagnetized at a temperature called Tcurie. When the magnet heats up to outside of Curie, it cannot recover once it has cooled. The ferrite magnet has a t-curie value of 460 degrees Celsius, a SmCo t-curie value of 750 degrees Celsius, and a neodymium-iron-boron t-curie value of 310 degrees Celsius.

3. 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 easily corroded. SmCo magnets are slightly less brittle and difficult to process, but have high corrosion resistance. SmCo magnets are also the most expensive magnet type. Ferrite magnets are less expensive than SmCo and NdFeB magnets and have good resistance to demagnetization and corrosion.

Summary: Ferrites and neodymium magnets each have different benefits. Ferrite magnets are easily magnetized. They are very resistant to corrosion and generally do not require additional coatings for corrosion protection. They are resistant to demagnetization from external magnetic fields. 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 from external magnetic fields.

The above is the difference between rare earth magnets and ferrite magnets introduced by Magnet For Concrete suppliers.

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