Samarium cobalt (Samarium cobalt 5 or Sm2Co17) and NdFeb (Nd2Fe14B) are both rare earth magnets – the strongest rare earth permanent magnets known.
They are called rare earths because both samarium and neodymium are found in lanthanide metals in the periodic table, and therefore the properties and crystal structure of these magnets are very similar.
Samarium is alloyed with the transition metal cobalt. Neodymium is alloyed with the transition metal iron. So each magnet is a combination of a rare earth metal and a transition metal.
Neodymium magnets also contain very small amounts of boron, which makes them different from samarium cobalt magnets because neodymium iron boron uses three main alloying elements, whereas samarium cobalt uses only two.
Rare earth magnets are the strongest permanent magnets known. They are used in many high-tech applications, such as electric drive motors for cars, smart speakers, smartphones (see our article on NdFeb magnets in smart speakers for smartphones and Internet of Things devices), sensors and more.
CWIEME Berlin was suspended by COVID in 2020 and 2021, our life and business were affected very much as well. We are very pleased to report that the restrictions around society and events in Berlin were relaxed on 01.04.2022. This reflects the reduction in the personal risk to individuals and means that mask wearing is no longer mandatory in exhibition halls (only now on public transport, in hospitals and nursing homes) and you no longer have to prove your covid status prior to entering public venues.
And we believe the community of CWIEME Berlin will be dedicated to delivering events and facilitating trade with health and safety at the top of the agenda.
U-POLEMAG as an exhibitor of CWIEME Berlin has been more than 8 years, we will take part in CWIEME Berlin as our industry event this year, and we will keep same Booth NO. 12A31 this time. Welcome to visit us and communicate any questions about magnets or magnetics. We look forward to meeting you on site at Messe Berlin in May.
Power rationing and forced cuts to factory production in China are widening amid electricity supply issues and a push to enforce environmental regulations.
The curbs have expanded to more than 10 provinces, including economic powerhouses Jiangsu, Zhejiang and Guangdong, the 21st Century Business Herald reported Friday. Several companies have reported the impacts of power curbs in filings on mainland stock exchanges.
Local governments are ordering the power cuts as they try to avoid missing targets for reducing energy and emissions intensity. The country’s top economic planner last month flagged nine provinces for increasing intensity over the first half of the year amid a strong economic rebound from the pandemic.
Meanwhile record high coal prices are making it unprofitable for many power plants to operate, creating supply gaps in some provinces, the Business Herald reported. If those gaps expand the impact could be worse than power curtailments that hit parts of the country during the summer. Zhejiang, about 160 energy-intensive companies in the textile, dyeing and chemical fiber industries have been ordered to halt production to meet energy consumption targets, Caixin reported. About 80% of the companies are in Ma’an, where a production halt order was issued from Sept. 21-30, the report said, citing an unnamed official.
Emergency power cuts were also ordered across 14 cities in the northern province of Liaoning after the grid suffered supply shortfalls, according to a notice on the local grid operator’s social media late Thursday. “Power suppliers will spare no effort to keep providing electricity to residents, hospitals, schools, radio, TV, telecommunications, transportation hubs and other important users,” the notice said.
Yunnan province is canceling electricity price discounts for aluminum smelters that made power costs about 16%-22% cheaper than industry average, according to a separate Caixin report. Yunnan Aluminum Co. last week said its production through the rest of the year will be significantly reduced because of provincial energy consumption controls.
The CSI 300 Utilities subgauge is up 19% this month, hitting the highest since late 2015 this week amid tight supply. Huaneng Power International Inc. and GD Power Development Co. are up at least 40% this month, leading on the subgauge, while smaller power stocks such as Zhongmin Energy Co. and Shanghai Electric Power Co. have added at least 70%.
The widening power curbs are also impacting agriculture, forcing the shutdown of several plants in Jiangsu and the northern port city of Tianjin that crush soybeans into oils used in salad dressings and margarine and meal used for animal feed, AgriCensus reported.
Neodymium Iron Boron Rare Earth Magnets are used everywhere and are one of the strongest permanent magnets available. But what exactly are they?
The Neodymium Magnet (also known as NdFeB, NIB or Neomagnet) is the most widely used type of Rare Earth Magnet. It is a permanent magnet which has been made from an alloy of neodymium, iron and boron to form the Nd2Fe14B tetragonal crystalline structure.
The first Neodymium Magnet was discovered in 1982 by General Motors and Sumitomo Special Metals as they investigated alternatives to the costly Samarium Cobalt Magnets. Since the discovery, the use of the Neodymium Magnet has touched everyone’s lives and can be found in items we use everyday like mobile phones, computers and even kitchen cupboard catches. They are also essential for renewable energy including wind turbines and electric
Neodymium Magnets are also help us recycle as a fundamental part of a Magnetic Separator or Eddy Current Separator as manufactured by Bunting Magnetics. The magnetic forces are used to both attract and repel metals to enable separation and recovery.
China dominates the global production of Neodymium Magnets (95%) due to the location of many of the reserves. At the end of 2010 and into 2011, the Chinese Government sent shock waves around the world when they slashed export quotas for Rare Earth Magnets and dramatically increased prices for foreign customers. It wasn’t until 2015, after China lost a World Trade Organization case brought by the USA and other trading partners, that the restrictions relaxed.
Neodymium Magnets are produced using two manufacturing methods:
• Classical powder metallurgy or sintered magnet process;
• Rapid solidification or bonded magnet process;
The Sintered magnet process produces a stronger and robust Rare Earth Magnet, but is more expensive to manufacture.
There is a enormous range of sizes and shapes of Neodymium Magnets for a diverse number of applications that continues to grow. There is no slowdown in the demand and there is only a question of supply and the price in the longer term.
From October, 2020 ,most of raw materials are keeping up-trend. Herein, we published the main materials price table as below, hope that it can be helpful and draw your attention that we see the market moving up
Recently, we have received same questions from downstream customers about the price increase of magnetic materials that some of them have puzzles and doubts about the problem. Therefore, we have made the following explanation with several main objective factors .
From October, 2020.China’s magnetic material industry has been affected by the international market, and the prices of bulk commodities have soared, especially the prices of rare earth, non-ferrous metals, iron ore, strontium ore and other raw materials. In addition, the multiple factors such as the domestic environmental protection concepts, cut or stop production of international iron and steel enterprises which have caused the price of magnetic materials have rocketed, and the supply is very tight.
For example, iron oxide has doubled from 2,000 CNY / ton in late last year to 4,000 CNY / ton, and in short supply now; FE-P has increased by 50% from 1,000 CNY / ton at the end of last year to 1,500 CNY / ton now; strontium carbonate has increased by 40% from 5,000 CNY/ ton to 7,000 CNY / ton now; cobalt oxide has increased by 12% from 190,000 CNY / ton to 230,000 CNY / ton, and the price of Pr Nd has also risen more than 50% . Judging from the development situation, the prices of these raw materials are still rising and stay high. The above mentioned materials are the main raw materials of magnetic products, accounting for more than 30% of the product cost, and permanent magnet products are even higher. The rising of raw materials cost from upstream will inevitably push up the price of magnetic materials. It is conservatively expected that the price will be pushed up by more than 10%, even higher. It is difficult for the industry itself to digest the rising cost of raw material prices, which needs to be absorbed in every link of the industrial chain.
China’s magnetic material industry has been very mature, product costs are transparent, technology and equipment of production factors have been finalized, so the profit is small, besides, the ability to self-digest the cost of raw materials is very limited, hope customers in the industry chain need to give understanding and sympathy. Of course, for the industry and enterprises, they should also dig deeper and make some sacrifices which through fine management and the development of new processes, new technologies, and new products to digest some of the rising cost pressure of raw materials. At the same time, everyone should communicate actively, do a good job in explaining it to the clients and obtain the understanding and support, and form a consensus on overall response to the unfavorable situation caused by the increase in raw material prices, and jointly maintain the smoothly and healthy development of China’s manufacturing industry.
What we don’t want to see is still coming. Recently, the price of rare earth raw materials has skyrocketed, rising by 20,000-50,000 yuan per day for several days in a row, and there is a high probability that it will continue to rise sharply in the future. This rapid increase is due to cash purchase of materials and shortage of supply, so the material factory has not quoted to the public.
The following figure shows the raw material price of magnets on November 25, 2020, and the price of praseodymium metal rises by 50000 yuan per ton.
Our company is unable to bear the continuously rising material cost. We have decided that from now on (November 25th), all new and old customers need to re-calculate the magnet price before placing an order. The quotation is valid on the same day, and the payment method should be advanced on the original basis.
●Magnetic recording media: VHS tapes contain a reel of magnetic tape. The information that makes up the video and sound is encoded on the magnetic coating on the tape. Common audio cassettes also rely on magnetic tape. Similarly, in computers, floppy disks and hard disks record data on a thin magnetic coating. ●Credit, debit, and automatic teller machine cards: All of these cards have a magnetic strip on one side. This strip encodes the information to contact an individual’s financial institution and connect with their account(s). ●Older types of televisions (non flat screen) and older large computer monitors: TV and computer screens containing a cathode ray tube employ an electromagnet to guide electrons to the screen. ●Speakers and microphones: Most speakers employ a permanent magnet and a current-carrying coil to convert electric energy (the signal) into mechanical energy (movement that creates the sound). The coil is wrapped around a bobbin attached to the speaker cone and carries the signal as changing current that interacts with the field of the permanent magnet. The voice coil feels a magnetic force and in response, moves the cone and pressurizes the neighboring air, thus generating sound. Dynamic microphones employ the same concept, but in reverse. A microphone has a diaphragm or membrane attached to a coil of wire. The coil rests inside a specially shaped magnet. When sound vibrates the membrane, the coil is vibrated as well. As the coil moves through the magnetic field, a voltage is induced across the coil. This voltage drives a current in the wire that is characteristic of the original sound. ●Electric guitars use magnetic pickups to transduce the vibration of guitar strings into electric current that can then be amplified. This is different from the principle behind the speaker and dynamic microphone because the vibrations are sensed directly by the magnet, and a diaphragm is not employed. The Hammond organ used a similar principle, with rotating tonewheels instead of strings. ●Electric motors and generators: Some electric motors rely upon a combination of an electromagnet and a permanent magnet, and, much like loudspeakers, they convert electric energy into mechanical energy. A generator is the reverse: it converts mechanical energy into electric energy by moving a conductor through a magnetic field. ●Medicine: Hospitals use magnetic resonance imaging to spot problems in a patient’s organs without invasive surgery. ●Chemistry: Chemists use nuclear magnetic resonance to characterize synthesized compounds.
Chucks are used in the metalworking field to hold objects. Magnets are also used in other types of fastening devices, such as the magnetic base, the magnetic clamp and the refrigerator magnet. ●Compasses: A compass (or mariner’s compass) is a magnetized pointer free to align itself with a magnetic field, most commonly Earth’s magnetic field. ●Art: Vinyl magnet sheets may be attached to paintings, photographs, and other ornamental articles, allowing them to be attached to refrigerators and other metal surfaces. Objects and paint can be applied directly to the magnet surface to create collage pieces of art. Magnetic art is portable, inexpensive and easy to create. Vinyl magnetic art is not for the refrigerator anymore. Colorful metal magnetic boards, strips, doors, microwave ovens, dishwashers, cars, metal I beams, and any metal surface can be receptive of magnetic vinyl art. Being a relatively new media for art, the creative uses for this material is just beginning.
●Science projects: Many topic questions are based on magnets, including the repulsion of current-carrying wires, the effect of temperature, and motors involving magnets.
●Magnets have many uses in toys. M-tic uses magnetic rods connected to metal spheres for construction. Note the geodesic tetrahedron
Toys: Given their ability to counteract the force of gravity at close range, magnets are often employed in children’s toys, such as the Magnet Space Wheel and Levitron, to amusing effect. ●Refrigerator magnets are used to adorn kitchens, as a souvenir, or simply to hold a note or photo to the refrigerator door. ●Magnets can be used to make jewelry. Necklaces and bracelets can have a magnetic clasp, or may be constructed entirely from a linked series of magnets and ferrous beads. ●Magnets can pick up magnetic items (iron nails, staples, tacks, paper clips) that are either too small, too hard to reach, or too thin for fingers to hold. Some screwdrivers are magnetized for this purpose. ●Magnets can be used in scrap and salvage operations to separate magnetic metals (iron, cobalt, and nickel) from non-magnetic metals (aluminum, non-ferrous alloys, etc.). The same idea can be used in the so-called “magnet test”, in which an auto body is inspected with a magnet to detect areas repaired using fiberglass or plastic putty. ●Magnets are found in process industries, food manufacturing especially, in order to remove metal foreign bodies from materials entering the process (raw materials) or to detect a possible contamination at the end of the process and prior to packaging. They constitute an important layer of protection for the process equipment and for the final consumer. ●Magnetic levitation transport, or maglev, is a form of transportation that suspends, guides and propels vehicles (especially trains) through electromagnetic force. Eliminating rolling resistance increases efficiency. The maximum recorded speed of a maglev train is 581 kilometers per hour (361 mph). ●Magnets may be used to serve as a fail-safe device for some cable connections. For example, the power cords of some laptops are magnetic to prevent accidental damage to the port when tripped over. The MagSafe power connection to the Apple MacBook is one such example.
5、Comparison of properties of various magnetic materials
When it comes to magnetic materials, we have to talk about “magnetism” first. Experiments show that any substance can be more or less magnetized in the external magnetic field, but the degree of magnetization varies. According to their properties in the external magnetic field, substances can be divided into five categories: paramagnetic substances, diamagnetic substances, ferromagnetic substances, ferromagnetic substances, and antiferromagnetic substances:
Paramagnetic substance: a substance which, when moved closer to a magnetic field, is magnetized according to the direction of the field, but is so weak that it can only be measured by precise instruments. If the applied magnetic field is removed, the internal magnetic field will return to zero, resulting in no magnetism. Such as aluminum, oxygen, etc.
Diamagnetic substance: a substance with a negative magnetic susceptibility. When subjected to an external magnetic field, the molecule generates an induced electron circulation, which generates a magnetic moment opposite to the direction of the external magnetic field. In other words, the direction of the magnetic field after magnetization is opposite to the direction of the external magnetic field. All organic compounds are diamagnetic, graphite, lead, water, etc.
Ferromagnetic substance: it is a kind of material which is magnetized under the action of external magnetic field, and still can maintain its magnetized state even if the external magnetic field disappears. Iron, cobalt and nickel are all ferromagnetic substances.
Ferromagnetic material: macromagnetism is the same as ferromagnetism, only with a lower magnetic susceptibility. Typical ferromagnetic material is ferrite. They differ most significantly from ferromagnetic materials in their internal magnetic structures.
Antiferromagnetic substance: inside an antiferromagnetic substance, the spins of adjacent valence electrons tend to be in opposite directions. The material has a net magnetic moment of zero and produces no magnetic field. This material is less common, and most antiferromagnetic substances exist only at low temperatures. If the temperature is above a certain value, it usually becomes paramagnetic. For example, chromium, manganese and so on have antiferromagnetism.
We call paramagnetic and diamagnetic substances as weak magnetic substances, and ferromagnetic and ferrous magnetic substances as strong magnetic substances. The magnetic material that says normally is to point to strong magnetic material commonly. Magnetic materials can be divided into:
Soft magnetic material: the magnetic material with low coercivity and high permeability can achieve the maximum magnetization with the minimum external magnetic field. Soft magnetic materials are easy to magnetize and easy to demagnetize. For example: soft ferrite, amorphous nanocrystalline alloy.
Hard magnetic material: also called permanent magnetic material, it refers to the material that is difficult to be magnetized and difficult to be demagnetized once magnetized. Its main characteristic is that it has high coercivity, including rare earth permanent magnetic material, metal permanent magnetic material and permanent magnetic ferrite.
Functional magnetic materials: magnetostrictive materials, magnetic recording materials, magnetoresistance materials, magnetic bubble materials, magneto-optical materials and magnetic thin film materials.
Since its introduction in the 1980s, NdFeB permanent magnet materials have been widely used in various fields such as automobiles, wind power, aerospace, and military industries with excellent magnetic properties. In recent years, the demand for wind power generation, new energy vehicles, etc. has continued to increase. This puts forward higher requirements for the coercive force and temperature stability of NdFeB permanent magnet materials.
Because the magnetic crystal anisotropy field of the Dy2Fe14B phase is much stronger than that of the Nd2Fe14B phase and the Curie temperature is relatively high, the coercivity and temperature stability of the material can be greatly improved. In sintered NdFeB materials, the content of rhenium is very high, and some can reach more than 10%. Everyone knows that the price of heavy rare-earth element europium is high, and a large amount of addition will increase the production cost of neodymium iron boron. Therefore, how to reduce the amount of europium under the premise of ensuring high coercivity and temperature stability has become an important issue.
The traditional element addition method is to add in the melting process, that is, Dy, Tb and Nd, Fe, B and other elements are smelted together, Dy distribution in the grain boundary and the main phase of the grain in the magnet. However, research shows that Dy at the grain boundary has the most significant effect on improving the coercive force, and the traditional method of adding elements is a “waste of resources”.
Japanese researchers first proposed the concept of “grain boundary diffusion”. They used a special process to make Dy exist only at the grain boundary and not enter the crystal by diffusion. This not only improved the performance of NdFeB materials, but also greatly reduced Dy. The total amount of elements reduces the cost of materials. They deposited Dy vapor on the surface of the particles during the milling process, and Dy atoms diffused along the grain boundaries during subsequent sintering. Dy and Fe located at the grain boundary are antiferromagnetically coupled, and the coercive force of the material increases from 800 kA / m to 1800 kA / m with almost no reduction in remanence.
Damage to the surface of the magnet after machining will weaken the magnetic properties, especially for small-size samples, the coercivity is significantly reduced, and grain boundary diffusion technology can be used to repair and increase the magnetic surface magnetic properties. At present, the grain boundary diffusion technology has received widespread attention, and its preparation processes mainly include evaporation diffusion, magnetron sputtering, surface coating, and the like.
Evaporation diffusion
The Dy / Tb evaporation process on the surface of the neodymium-iron-boron magnet is to place the heavy rare earth element or its compound and the original sample to be processed in a steaming furnace, and use high temperature heating to evaporate the heavy rare earth element at high temperature. It is deposited on the surface of the original magnet and diffuses into the magnet along the grain boundary.
The evaporation diffusion method can simultaneously perform sublimation of Dy evaporation source, deposition on the surface of neodymium-iron-boron, and diffusion in the magnet under the condition of high temperature heating. The advantage of using the evaporation diffusion method is to diffuse heavy rare-earth elements. It is more sufficient to reduce the amount of heavy rare-earth elements and reduce the cost, thereby successfully preparing a high coercivity and low rare-earth content neodymium-iron-boron magnet.
Magnetron sputtering
Unlike the evaporation diffusion method described above, magnetron sputtering separates the Dy deposition process from the diffusion process. It deposits Dy on the surface of the original magnet by physical sputtering, and then performs high temperature diffusion. Magnetron sputtering has the advantages of uniform film thickness and obvious coercive force enhancement effect.
Some research experiments have shown that after sintered and tempered N35 magnets are treated with sputtering Dy, the coercive force is greatly improved when the remanence is reduced by only 0.009T and 0.03T, which are increased by 708.44kA / m and 665.46, respectively. kA / m, the increase rate is as high as 73.5% and 64.8%, and the average mass fraction of Dy element of the magnet after Dy infiltration does not increase by more than 0.4%. After infiltrating the Dy-treated magnet, Dy is enriched in a continuous band at the Nd-rich phase, which makes the Nd-rich phase more continuous and smooth. The improvement of the Nd-rich phase structure and morphology is one of the reasons for the increase in coercive force. The (Nd, Dy) 2Fe14B epitaxial layer formed has a large magnetic crystal anisotropy field, and the hardening of the grain epitaxial layer can better suppress the reverse domain nucleation, which is also the main reason for the increase of coercive force.
Surface coating
The surface coating method refers to coating a rare earth compound directly on the surface of the original magnet sample, and performing a high-temperature heat treatment diffusion in a rare gas atmosphere after drying treatment. Using this method can significantly improve the coercive force of the magnet, the advantage is that the process is simple and convenient, the disadvantage is that it is easy to cause uneven coating and insufficient diffusion.
Magnetic Field Calculation
Raw Material Trend
Magnet Testing
Magnet Plating
Magnetization
Magnet Packing for Shipment
Magnetic Glossary
Magnets Overview
Magnets FAQ'S
Alibaba Trade Assurance
