Types of Permanent Magnet Materials

At present, the common permanent magnetic materials are ferrite, NdFeB, samarium cobalt, aluminium nickel cobalt, rubber magnetism and so on.
Each of the above magnets has its own characteristics and different application fields. The following are briefly introduced:
Ferrite magnet
Ferrite is a non-metallic magnetic material, also known as magnetic ceramics. We take apart the traditional radio. The horn magnet inside is ferrite. At present, the magnetic energy product of ferrite is only slightly higher than that of 4MGOe. One of the greatest advantages of this material is its low price. At present, it is still widely used in many fields. Ferrites are ceramics. Therefore, the machinability is similar to that of ceramics. Ferrite magnets are molded and sintered. If processing is needed, only simple grinding is needed. Because it is difficult to machine, most ferrite products are simple in shape and large in size tolerance. The square shape product is good and can be ground. Other dimensional tolerances are given as a percentage of nominal size. Because ferrite is widely used and inexpensive, many manufacturers will have ready-made circular rings of conventional shapes and sizes, such as diamonds and other products to choose from. Because ferrite is made of ceramics, there is basically no corrosion problem. The finished product does not need surface treatment or coating such as electroplating.

Permanent Magnet Materials
Rubber coated magnet
Rubber magnet is one of the series of ferrite magnets. It is made of bonded ferrite magnetic powder and synthetic rubber by extrusion, calendering and injection molding. It can be processed into the strip, roll, sheet, block, ring, and various complex shapes. Its magnetic energy product ranges from 0.60 to 1.50 MGOe in the application fields of rubber magnets: refrigerators, message boards, fasteners that fix objects to metal bodies for advertising, and magnetic discs for toys, teaching instruments, switches, and sensors. Mainly used in micro and special motors, refrigerators, disinfection cabinets, kitchen cabinets, toys, stationery, advertising, and other industries.

Samarium cobalt
Samarium-cobalt magnets consist mainly of samarium and cobalt. Samarium cobalt magnets are also the most expensive of several magnets because of the high price of the two materials themselves. The magnetic energy product of samarium-cobalt magnet can reach 30MGOe or even higher at present. In addition, samarium cobalt magnets have high coercivity and high-temperature resistance. They can be used at 350 degrees Celsius, so they can not be replaced in many applications. Samarium cobalt magnet belongs to powder metallurgy products. Generally, according to the size and shape of the finished product, the manufacturer sinters the block blank and then uses the diamond blade to cut into the finished product size. Because samarium cobalt is conductive, it can be processed by wire cutting. In theory, samarium and cobalt can be cut into shapes that can be cut by wire cutting, without considering magnetization and larger size. Samarium cobalt magnet, corrosion resistance is good, generally, do not need to carry out anti-corrosion plating or coating. In addition, the texture of samarium cobalt magnet is very brittle, so it is difficult to process small size or thin-walled products.

The neodymium magnet is a magnet product with wide application and rapid development. Neodymium iron boron has been widely used since its invention, and it has not been more than 20 years. Because of its high magnetic properties and processability, the price is not very high, so the application field expands rapidly. At present, the magnetic energy product of commercialized NdFeB can reach 50MGOe, which is 10 times that of ferrite. NdFeB is also a powder metallurgical product, and its processing method is similar to that of SmCo. At present, the highest working temperature of NdFeB is about 180 degrees Celsius. If it is used in harsh environments, it is generally recommended not to exceed 140 degrees Celsius. NdFeB is very susceptible to corrosion. Therefore, most of the finished products need to be electroplated or coated. Conventional surface treatments include nickel plating, zinc plating, aluminum plating, electrophoresis, etc. If working in a closed environment, phosphating can also be used. Because of the high magnetic properties of NdFeB, NdFeB has been used to replace other magnetic materials on many occasions to reduce the volume of products. If we use ferrite magnets, the size of mobile phones today will not be less than half a brick.
Samarium cobalt magnet and neodymium iron boron magnet have better processing performance. Therefore, the dimension tolerance of the product is much better than that of ferrite. General products, size tolerance can be achieved (+/-) 0.05 mm.

Aluminum-nickel-cobalt magnet has two processes: casting and sintering. AlNiCo magnets have a magnetic energy product of up to 9MGOe, which has the greatest characteristic of high-temperature resistance and working temperature of 550 degrees Celsius. However, Al-Ni-Co is very easy to demagnetize in reverse magnetic field. If you push two poles of Al, Ni, and Co together, the magnetic field of one of the magnets will be withdrawn or reversed. Therefore, it is not suitable to work in the reverse magnetic field (such as magnet rotor). Aluminum, nickel, and cobalt have high hardness. Although they can be ground and cut by wire, they are expensive. Generally supplied products, there are two kinds of ground or non-grinded. Aluminum, nickel, and cobalt are widely used in the sensor field.

Neodymium Strong magnet VS Common Magnet

Although many people know about magnets, they do not know that magnets can be divided into many kinds. Moreover, there are great differences between “ordinary magnets” and “Neodymium strong magnets“. Magnets used in different industries are also very different.

cylinder magnet

1. According to the material, magnets can be divided into Nd-Fe-B magnets, ferrite magnets, samarium-cobalt magnets and AlNiCo magnets. Among them, the popular ones are Nd-Fe-B magnets, which are called “the king of magnets” because of their super-strong magnetic force.

ring magnets

2. According to magnetism, it can be divided into permanent magnet and ordinary magnet.

3. According to the magnetic force, it can be divided into strong magnet and ordinary magnet.

black plastic coated magnet

So what are the differences between ordinary magnets and neodymium strong magnets?

custom strong magnet

1. High temperature resistance: The indoor temperature and Curie temperature of Nd-Fe-B magnets are higher than those of ordinary magnets. No matter which kind of strong magnet material is used, it is better than ordinary magnet, so the limit temperature of strong magnet itself can be greatly increased. In the industrial industry, the machine can run at high temperature.

2. Hardness: Because Nd-Fe-B magnets increase the density of rare elements, they will be harder in hardness than ordinary magnets. Therefore, in the use process, it greatly avoids the situation of fragmentation of magnets caused by collision, while ordinary magnets are fragile, and their appearance will rust over a long period of time.

neo custom magnets

3. Strong magnetism: Common magnets on the market are determined by the amount of coins they can absorb, while NdFeB strong magnets can absorb 640 times their own weight, and the magnetic force can be imagined to be how big, so when contacting strong magnets, attention should be paid to avoid being pinched by them.

4. Price: Although the magnetism of NdFeB magnet is very strong, its price is proportional to itself.

In summary, there is still a significant gap between neodymium magnets and ordinary magnets. Nd-Fe-B magnets are generally used in electronics and other industries.

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Is Neodymium Harmful to Humans

I. Historically Magnetized Water
Magnetism is one of the four fundamental forces in nature. The compass in modern China is an example of the ingenious use of magnetism.

2. Neodymium magnets, High Strength Magnet King
In 1983, the third generation of NdFeB, Na-Fe-B came out. Its magnetic field strength is more than ten times that of ordinary magnets. Its service life is over ten years. It is the highest permanent magnetic data of magnetic energy product (MGOE) discovered by human society so far, and it is known as the “King of Permanent Magnets“. It is widely used in national defense, aerospace technology, microwave, communication, electronics, medical care, and other high-tech areas.

High Strength Magnet King

3. Scale removal and scale prevention of neodymium
After neodymium high-intensity magnetization treatment of water, the angle and length of water molecule bond deformed simultaneously. The hydrogen bond angle decreased from 105 degrees to 103 degrees, resulting in a series of changes in the physical and chemical properties of water. The activity and solubility of water improved greatly. Calcium carbonate in water decomposed into lower solid calcium bicarbonate in the cooking process, which was not easy to accumulate on the wall and was easily carried away by water. In addition, the degree of polymerization of water improves, and the dissolved solid material becomes finer particles. When the particles are refined, the distance between the two ions is smaller, and it is not easy to condense on the wall, so as to achieve the effect of scale removal.

Magnet King

4. Neodymium Health Care Principle for Dispelling Diseases
Due to the difference of geographical environment and mineral content in water, harmless substances in water have a great impact on our life and health. Calcium salts and magnesium salts in water are insoluble, affecting the absorption and Photosynthesis of plants and animals. A large number of theoretical and scientific experiments have proved that NdFeB high-intensity magnetization can change the external tension, density, solubility of water, and seriously affect the chemical properties such as acid and alkali. Magnetized water can add the activity of enzymes in water and the permeability of biofilm, often drinking can strengthen health care and improve human immunity, prevent and treat a variety of diseases.

After high-intensity magnetization of water, water molecules are activated and oxygen content is high:
1. Regular drinking can add permeability of biofilm, reduce blood thinning, adhere to vascular elasticity, avoid thrombosis, prevent and dissolve stones;
2. Regular drinking can strengthen the body, improve human immunity, resist aging, prevent and treat many diseases, slow down and promote the aging of human epidermis, commonly used. It can make your skin smooth, tender and beautiful.

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Poles of Spherical Magnets

We know that the poles of bar magnets are actually at both ends, and the poles of horseshoe magnets are at both ends. But what about spherical magnets? If one is in the center of the sphere, one is in some part of the surface or on the sphere, it is obviously not tenable, because, in this way, there is no magnetic field around the spherical magnet. If we say that there are two relative points on the sphere, then obviously there can be countless magnetic poles, which is also impossible.

In fact, the magnetic poles of neodymium sphere magnets in nature are usually at both ends of a certain diameter, such as the NS poles of the earth. Of course, there may be a slight deviation, but it will not be much worse in general. As for artificial spherical magnets, their poles are related to the direction of magnetization during manufacture. There are many kinds of materials for artificial magnets, but no matter which kind of material is made into a certain shape and then magnetized. Therefore, its magnetic pole position is determined by the magnetizing method. When the direction of magnetization is determined, the magnetic poles are at both ends of the sphere diameter in that direction.

magnetic poles

We can also think about it through an ideal experiment. If a bar magnet is separated symmetrically from left to right by a straight line from N to S, then a very small piece is cut off on the left side and a very small piece is cut off on the right side at the same time. Then the remaining large N and S poles remain primitive. Repeat the action until the magnet is spherical. At this time, the magnet must still retain the original orientation of N and S poles. That is to say, the magnetic pole of a spherical magnet should be the same as the magnetic field of the earth, in effect, as a long magnet. The magnetic force line emits from the N pole and forms an arc in the outer space, pointing to the S pole. Inside the magnet, the line of force points from the S pole to the N pole.

ball magnets

Similarly, the external magnetic field of a hollow spherical magnet is the same as that of a solid sphere, and the magnetic poles are distributed at opposite poles. In the internal space, it is also a polar magnetic field.

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Elevator Lifting Equipment-Electromagnet

The development of the elevator has brought great convenience to the life of contemporary people. Then the elevator lifting equipment electromagnet, its main part, namely crane, lifting machinery is widely used in lifting, transportation, loading and unloading, installation and personnel transportation of various materials in modern industrial production indispensable equipment. Crane is a kind of mechanical equipment that lifts, drops and moves materials by means of lifting hooks or other lifting devices in intermittent and repetitive working mode.
The limiter of elevation, limit of operation, buffer, an anchoring device, rail clamp or windproof shoe, safety plate, anti-tilt device, lifting weight limiter, moment limiter and anti-collision device, etc.

Elevator Lifting Equipment

The Most Important Accessories of Elevator Lifting Equipment Electromagnet
Elevator lifting equipment electromagnet is a new type of magnetic lifting equipment for magnetic conductive materials such as steel plate, ingot, and scrap steel, which has strong practicability. Lifting electromagnet does not need to bind scattered materials and other treatments when lifting and transporting materials, so it is also called bulk lifting electromagnet, which is very suitable for lifting and transporting scattered scrap steel and scrap. Lifting electromagnet is the usual electromagnetic sucker for lifting.

Working Principle of Elevator Lifting Equipment Electromagnet
Elevator lifting equipment electromagnet is based on the principle of electromagnetic conversion, in the state of electrification to produce strong electromagnetic attraction, in order to control the moving or stopping state of the object. The structure of the electromagnet is reasonable and compact. The coil is placed in the soft magnetic material shell and sealed with epoxy. It has the characteristics of small size, large suction, firm, reliable, fully sealed and strong environmental adaptability. The series of electromagnets can be operated remotely with simple and sensitive action and stable and reliable function.

Applicable scope of elevator lifting equipment electromagnet: AC rated working voltage of lifting electromagnet is 220 volts. Normal temperature type lifting electromagnet is suitable for handling ferromagnetic materials whose surface temperature is below 100 C. High-temperature type lifting electromagnet is suitable for handling ferromagnetic materials whose surface temperature is below 600 C.

The function of elevator lifting equipment electromagnet is to produce strong magnetism under the condition of electrification, to absorb metal objects, and then carry them by crane. Without electricity, there is no magnetism, which is different from the permanent magnet. The advantage is that magnetism can be controlled at any time and send and receive freely.

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What Do Magnets Do

Magnets consist of iron, cobalt, nickel and other atoms. The internal structure of the atoms is quite special, and they have magnetic moments themselves. Magnets can generate magnetic fields and have the characteristics of attracting ferromagnetic materials such as iron, nickel, cobalt and other metals.


Different magnets have different uses.

Classification of magnets:

Shape magnets: block magnet, arc magnet, special magnet, cylindrical magnet, ring magnet, disc magnet, bar magnet, magnet frame magnet.

Attribute magnets: samarium cobalt magnet, neodymium magnet (strong magnet), ferrite magnet, aluminium nickel cobalt magnet, ferrochromium cobalt magnet.

Industry magnets: magnetic components, motor magnet, rubber magnet, plastic magnet and so on.

Magnets are divided into permanent magnets and soft magnets. Permanent magnets are added with strong magnets, so that the spin of magnetic materials and the angular momentum of electrons are arranged in a fixed direction, while soft magnets are added with electricity. (It’s also a way to add magnetism) If the soft iron is removed by the equal current, it will gradually lose its magnetism.

shape magnets

Use of different types of magnets:

1. Nd-Fe-B permanent magnet is a modern magnet with strong magnetism and is widely used.

It is mainly used in electroacoustics, permanent magnet motors, communications, automotive electronics, magnetic machinery, aerospace, computers, household appliances, medical devices, office automation, toys, packaging boxes, leather products, magnetic accessories, and other fields.

2. Permanent magnet ferrites are used as constant magnets in meters, generators, telephones, loudspeakers, TV sets and microwave devices. They are also used in recorders, pickups, loudspeakers, magnetic cores of various instruments, radar, communication, navigation, telemetry, and other electronic devices.

3. Samarium-cobalt magnets have been widely used in detectors, generators, radar, instrumentation, and other precision science and technology fields because of their high working temperature of 300 degrees, corrosion resistance and oxidation resistance.

4. Aluminum-nickel-cobalt magnets are heat-resistant and corrosion-resistant. They are mainly used in motors, sensors, medical instruments, hand tools, loudspeakers, and various instruments.

5. Rubber coated magnets are different and heterosexual, and their homosexual attraction is weak. They are mainly used for propaganda (refrigerator stickers, car stickers, etc.), decorative gifts, refrigerator stickers, toys, teaching materials, etc. Heterosexual magnets can be used in small motors, sensors, magnetic adsorbents, etc.

Understanding the use of different magnets is very important for enterprises. Making full use of the characteristics of different magnets can better improve product performance.

Anything You Should Know About NdFeB magnets

1. What are the applications of Nd-Fe-B magnets?

Neodymium permanent magnets are rapidly developing and widely used because of their excellent properties, abundant raw materials, and reasonable prices. It is mainly used in micro-motor, permanent magnet instrument, electronic industry, automobile industry, petrochemical industry, nuclear magnetic resonance device, sensors, Halbach Arrays, audio equipment, magnetic levitation system, the magnetic transmission mechanism, and magnetic therapy equipment.

magnetism neodymium magnet

2. What materials are NdFeB made of?

The main materials of the Nd-Fe-B permanent magnet are rare earth metal Nd (32%), metal element Fe (64%) and non-metal element B (1%) (a small amount of Dy, Tb, Co, Nb, Ga, Al, Cu, etc.). Neodymium ternary permanent magnets are based on Nd2Fe14B compound, whose composition should be similar to that of Nd2Fe14B compound. However, when the composition of Nd2Fe14B is completely proportioned, the magnetic properties of the magnet are very low, even no magnetism. It is only when the content of Nd and B in the actual magnet is more than that of the Nd2Fe14B compound that better permanent magnet performance can be obtained.

3. How long can the magnetic properties of NdFeB last?

Neodymium magnets have high coercivity, and there will be no demagnetization and magnetic changes in the natural environment and general magnetic field conditions. Assuming that the environment is suitable, the magnetic properties of the magnet will not be greatly damaged even after a long time of use. So in practical applications, we often neglect the influence of time factor on magnetic properties.

4. What is the direction of the rare earth magnet?

The direction in which the magnet with anisotropic orientation can obtain the best magnetic properties is called the orientation direction of the magnet. The magnet is divided into:

a. Isotropic magnets: magnets with the same magnetic properties in any direction

b. Anisotropic magnets: The magnetic properties will be different in different directions, and there is a direction, i.e. orientation direction, in which the magnets with the highest magnetic properties are obtained. Sintered NdFeB permanent magnets are anisotropic magnets, so it is necessary to determine the orientation (magnetizing direction) before production.

5. Factors affecting the magnetism of neodymium magnets

Because sintered NdFeB is very sensitive to working temperature, the instantaneous maximum temperature and the continuous maximum temperature of the environment may produce different degrees of demagnetization for magnets, including reversible and irreversible, recoverable and irreversible.

6. What is the working temperature range of neodymium magnets?

Temperature limitation of Nd-Fe-B magnets has led to the development of a series of grades of magnets to meet different operating temperature requirements. Please refer to our performance catalog to compare the operating temperature ranges of different grades of magnets. It is necessary to confirm the maximum operating temperature before selecting neodymium magnets.

Multiple Uses of Neodymium Disc Magnets Domestically

Neo magnets are super strong and very useful all around the house, office and workshop. Neodymium disc magnets are particularly sold for domestic use. Although they are small, these discs are still very hazardous and should be handled with care and kept out of reach of children.

neo disc magnets

Additionally, one should handle separate magnets with care as they can snap back and pinch the skin. An NdFeB disc is a permanent magnet that will retain its magnetism for several years. This is particularly if used in a favorable environment that cannot interfere with its plating or coating. They are made of neodymium, iron and boron and this is the strongest manmade alloy. A neodymium disc magnet, as mentioned above, has many uses around the office, house, garage or workshop. Some of the uses are summarized as shown below.

• Door catches. Small neodymium disc magnets are capable of pulling a twisted cabinet door straight. It can also hold it locked
• Use on fixtures, hardware and jigs
• Hanging items. These magnets are so strong that they can even be used on a corner dry wall that has a metal core.
• Neo disc magnets can be used in wood and other surfaces as long as they are backed by steel.
• Refrigerators
• Holding tools on the edge of a workbench for easier retrieval

Neodymium disc magnets should be kept from electronic devices such as, televisions, computer hard discs, floppy discs, cassette tapes, bank cards, credit cards and related items. This is because their strong magnetic fields can wipe out data on some of the electronic items mentioned above as they store it magnetically. Because drilling, screwing and machining these small items is a sensitive task, it should be done professionally.  Neodymium is very breakable even though hard. So if machined with the wrong equipment it can break easily and become waste.

To attach these discs to a particular surface use special adhesives made for use with neodymium magnets. Epoxy glue could also be used. Finally, customers should pay attention to the sizes of NIB magnets. These will depend on the applications one has. One thing is for sure though, that a very tiny neo disc magnet will hold an item that is two or more times heavier. One will find that the pull force of each magnet is indicated. For instance, neodymium disc magnets measuring ¼ x1/10 inches have magnetic strength of 2.5 lb.

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Permanent Magnet Materials for Wireless Charger

The main types of the magnetic materials are widely applied in wireless charger at present are NdFeB permanent magnets, NiZn ferrite thin disk, MnZn ferrite thin disk, soft ferrite magnetic stripe.

As the main components of wireless charging technology, a variety of absorbing material disks made of soft magnetic ferrite materials play a role of increasing induced magnetic field and shielding interference of coil. The requirement for performance, size, and reliability of soft magnetic ferrite materials is rather high in wireless charger. Nevertheless, the receiving end has a higher requirement.

Wireless Charger

Multi-coil free position type charger can work with multi-terminal at the same time. There are a number of coils arranged in its internal covered most area of the charging dock. Thus, the terminal can be freely placed in the charging dock; the charger will automatically select several efficient transmission coils to work. The working frequency is 105 kHz to 113 kHz for this type charge according to QI standard regulation. Absorbing material disk uses high Bs and low loss characteristics of MnZn power materials.

According to the way of receiver placement, wireless charging transmitter is divided into fixed position type, single coil free position type and multi-coil free position type. These transmitting terminals have different requirements for ferrite products.

Fixed position type charger applied NdFeB permanent magnet as positioning, terminal equipment must be placed on the fixed position to charge and maximize the charging efficiency. In this charger design, work frequency is 110 kHz to 205 kHz based on QI standards. The resonance frequency of fixed position type charger is high, generally using low loss, high-frequency magnetic shielding NiZn ferrite chip as a separate disk.

For single coil free position type charging equipment, there is a drive device in the internal coil which allows plane mobile. Through setting position from the automatic detection device, moving the coil to this position, making the position of the coil in line with the position of terminal receive, eventually realize charging and increasing the charging efficiency. With this design, the receiver can be placed at any position on the charging panel. Based on the QI standard, the working frequency is 140 kHz for this charger. Due to movement requirement of the coil, absorbing material disk must be high reliability. It needs to use a flexible magnetic disk produced by the taper-casting process.

Permanent magnet materials applied to the wireless charging system, on the one hand, enhance magnetic flux between transmit and receive coil, improve transmission efficiency; on the other hand, as a positioning device between transmitting and receiving, facilitate fast and exact positioning of the terminal. Small wireless charging equipment mainly uses NdFeB permanent magnet materials; large wireless charging equipment can use ferrite magnets instead of neodymium permanent magnet materials to reduce the cost.

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NdfeB Magnets for Electrical Fields

With the increasing performance of permanent magnet materials, rare earth permanent magnet materials are widely used in electrical fields.
Using high-performance rare earth permanent magnet materials to make a motor, the structure does not require special electrical excitation system, which helps to improve motor efficiency and power factor, and save energy, to reduce the size of the motor.

electrical motor
Currently in the design of permanent magnet motor, the general assumption that a uniform distribution of the various parts of the magnetic field of the permanent magnet and the magnetic properties of the same batch of neodymium magnets can be the same, while the need to use a permanent magnet demagnetization curve of permanent magnet at room temperature under suppliers, intrinsic connectivity magnetic parameters, residual magnetism, such as density and maximum energy product.

However, since the manufacturing process and the level of the plant and other reasons, there is a temperature in each portion of a permanent magnet hereinafter actual performance differences and the performance of the same group of permanent magnets is different.

The magnetic properties of the permanent magnet
The permanent magnet motor in normal operation can be closely related to the magnetic permanent magnet.
The strong magnet motor can directly determine whether reliable operation.
When the permanent magnet motor is running, sometimes the rotor temperature is high and NdFeB irreversible demagnetization will happen, causing permanent magnet synchronous motor efficiency and power factor and other performance indicators deteriorated.