21/04/2020
10 Tips of General Knowledge of Neodymium magnet.
1. Is the neodymium magnet iron?
Many people think that neodymium magnets are iron, but they are not. Magnetite has magnetic and its main component is Fe3O4. There are many kinds of artificial magnets, and the stronger one is the artificial neodymium magnet. It is a permanent magnet. In terms of the manufacturing process, the cost of iron is much lower. The neodymium magnet is a rare earth. This material is relatively expensive. In this sense, the magnet is not iron.
There are two main types of magnetic materials. The first is permanent magnetic materials (also called hard magnets): the material itself has the characteristics of preserving magnetic force; the second is soft magnetic (also called electromagnet): it needs external power to generate magnetic force. There are also two major categories of permanent magnet materials. The first category is: alloy permanent magnet materials include rare earth permanent magnet materials (Nd2Fe14B), samarium cobalt (SmCo), neodymium nickel-cobalt (NdNiCO); the second category is: According to different production processes, ferrite materials (Ferrite) is divided into Sintered Ferrite, Bonded Ferrite (Rubber Magnet), Injection Ferrite. The orientation of the magnetocrystals is divided into isotropic and anisotropic magnets.
2. How can magnet manufacturers detect the performance and quality of NdFeB magnets?
Neodymium iron boron magnets with samples generally use micrometers, vernier calipers, gauss meters, magnetic flux meters, film thickness meters, and other measuring tools.
Micrometers and vernier calipers mainly measure the tolerance size of NdFeB magnets in mm.
The Gauss meter mainly measures the magnetic force of a point on the surface of the magnet. The unit is Gauss. Since the magnetic force of each point on the surface of the magnet is different, and the edge magnetic force is higher than the magnetic force of the center point, the measured data error is too large. Generally, the central magnetometer prevails.
There is also magnet electroplating. This visual inspection is sufficient. The quality of the coating directly affects the service life of NdFeB.
The main methods for detecting the quality of NdFeB coating are:
Appearance visual inspection, coating thickness measurement, drop test (mainly for galvanized products), cross-cut test (generally used for nickel-plated products), chilled shock test, PCT pressure test, SST salt spray test, constant temperature, and humidity test, etc.
The film thickness gauge mainly measures the thickness of the electroplated layer of the finished NdFeB magnet. The use of the film thickness gauge can effectively monitor the quality of the electroplating quality. The magnet can be flexibly adjusted when electroplating.
The last magnetic flux meter, which mainly measures the magnetic force of one side of the neodymium iron boron magnet, is the unit of Weber Wb. Compared with the Gauss meter, the data measured by the magnetic flux meter is more objective and accurate. Generally, magnet manufacturers choose a magnetic flux meter to detect finished NdFeB magnets.
If the requirements on the magnet are relatively high, the most accurate method is to use a demagnetization curve analyzer to measure the magnetic properties of the magnet.
3. Introduction to the difference between multi-pole magnetization and ordinary magnetization.
In a nutshell, ordinary magnetization uses existing magnetization equipment and fixtures to magnetize magnetic materials. After magnetization, the product exhibits N and S poles.
Multi-pole magnetization is to use a customized magnetization fixture for magnetization. After magnetization, multiple N and S poles can be displayed on a plane. Due to the use of specially designed specifications and pole magnetization fixtures, It will be generated the cost of the additional magnetization fixture.
The following picture shows the common magnetization (magnetization) method of the magnet:
4. Where are magnets used?
The question of where the magnet is used is not enough in a few words. The application of the magnet involves almost all walks of life. Let me talk about it separately.
1) Surroundings of life
The mobile phone in our hand, the holster of the mobile phone, the bag on the back of the body, the headphones to listen to the song, the TV that I watch every day, the electric toothbrush that gets up to brush my teeth in the morning, the electric razor, the door cleaner on the wall, etc.
2) Packaging products
Such as mobile phone box, moon cake box magnet, tea box magnet, wine box magnet, storage box magnet, etc.
3) Hardware products
Mold magnets, magnetic chucks, mechanical magnets, electronic product accessories, etc.
4) Electronic products
Permanent magnet mechanism vacuum circuit breaker, magnetic holding relay, electric meter, water meter, sound meter, reed switch, sensor, etc.
5) Electrical products
Electric fan magnet, rice cooker magnet, magnetized water purifier magnet, electronic coffee machine magnet, etc.
6) Photoelectric products
Camera magnet, lens magnet, etc.
7) Magnetic attraction products
Magnetic data cable magnet, magnetic connector magnet
8) Electric products
VCM, CDDVD-ROM, generator, motor, servo motor, micro motor, motor, vibration motor, etc.
9) Electroacoustic products
Speakers, receivers, microphones, alarms, stage audio, car audio, etc.
10) mechanical equipment
Magnetic separation, magnetic separator, magnetic crane, magnetic machinery, etc.
11) Medical care
MRI instrument, medical equipment, magnetic therapy, and health care products, magnetized fuel-saving devices, etc.
12) Toy magnet
Some toys made of magnetic materials, such as darts, magnetic drawing boards, magnetic building blocks, etc.
5. Does n52 have any requirements for the shape of the magnet?
N52 does not require the shape of the magnet. The shape can be round, disc, cylinder, ring, countersunk, arc, square or special-shaped, etc., depending on customer requirements.
Our factory can customize the shape, specification and surface treatment according to your design requirements. If there is a temperature resistance requirement, tell us how much we need to withstand (n52 conventional temperature resistance is 80 degrees). We choose the appropriate material for you to save costs for you. It is best to provide drawings for our factory to check the price!
6. Where are NdFeB thin-film magnets generally used?
NdFeB flakes with a thickness of about 0.5mm are better for production,
The use of sheet magnets is very wide. Sheet magnets are widely used in packaging, hardware accessories, brushless motors, permanent magnet instruments, medical equipment, magnetic therapy equipment, audio equipment, magnetic suspension systems, and magnetic transmission mechanisms, etc.!
What are the advantages of sheet magnets?
Strong suction: It is well used in various packaging boxes and shells. Although it is small, a high-performance magnet can provide a super-strong magnetic energy product of 41.8kj / m3 and a residual magnetization of 460mT, making Wrapped gift shells can be firmly absorbed without falling.
Small size: The use of thin magnets with a volume of only a few millimeters does not affect the appearance of the product itself in appearance, and preserves the integrity of the product.
7. Can the specifications of your powerful magnets be made according to my requirements?
I believe many people will have such doubts. The specifications of powerful magnets can be customized according to customer requirements, and some of the more conventional sizes generally have no problems. But there are several situations to look at.
1) If the size is too large, it depends on the specific size and the company's production conditions. We also have orders for NdFeB magnets with relatively large magnetic rings. Ring specifications of more than 100 mm are acceptable. Of course, the larger the size, the higher the price. The price of NdFeB is affected by performance, specifications, shape, tolerance, size, etc. The higher the requirements of these factors, the more expensive the price will be.
2) If the size is too small, the requirement for accuracy will be higher. It is also affected by the specifications, shape, size, etc. of the magnet. If these requirements are more, the price will be higher.
3) Irregularly shaped neodymium magnets are magnets with special shapes. When custom-made strong magnets, if they are some special shapes, we need to send drawings and samples to our manufacturer.
4) Customization of powerful magnets If the quantity is large, the price will be advantageous. If the quantity is small, considering the artificial material resources, there is no advantage of a large quantity in price. Therefore, pay attention to the influence of these factors when customizing NdFeB. ROBO Magnetic has a professional production R & D team, you can contact us with customized magnet needs, we can serve you more professionally. We need to meet the magnet size you need.
If you need a strong magnet, or other magnets quotation, please send an email to sales@robomagnetic.com, we will contact you immediately.
8. What are the machining features and procedures of sintered NdFeB products?
Due to the influence of production factors, the dimensional accuracy of NdFeB blanks cannot directly meet the customer's requirements, and subsequent processing must be performed to meet the customer's requirements. For some special-shaped or slicing machines that can not be sliced directly by wire cutting (wire cutting machine); for wafers and small and medium squares with slicing machines, for higher precision or CPK requirements, double-sided grinding machines are also required (slicing machine, double Surface grinder); small cylinders that cannot be directly pressed need to be cut into small squares with squares and then rounded (small centerless grinding); some products require small holes to be drilled, and holes with a diameter of more than 6mm can be sleeved Machine, sleeve hole machine); the shaped and pressed cylinder (below Ф80) is processed with a centerless grinder (centerless grinder); cylinders larger than 80mm are generally completed with sleeve hole equipment; blocks that need to be ground are large vertical mills or Grinding, or double-sided grinding equipment; some special-shaped products can also be completed by direct bushing; for large products, manual chamfering is generally used, and small products use electroplating vibration chamfering.
9. Why do NdFeB magnets need to be chamfered?
The chamfering of the neodymium magnet is the previous process of electroplating, mainly to grind the right angle of the product periphery to a certain arc according to customer requirements, and at the same time make the surface of the black sheet smoother, increase the adhesion of the electroplated layer, and make the plated surface after electroplating smoother.
1) How long does the magnet chamfer?
The cut black non-plated neodymium magnet is put into a chamfering machine for chamfering, which usually takes more than half a day.
2) What is the effect of not chamfering NdFeB magnets?
Without chamfering, electroplating will not be possible, or the electroplated surface will fall off easily, affecting the quality.
3) What machine is used to chamfer the NdFeB magnet?
The chamfering machine is used, and the chamfering is ground by vibration
Not only NdFeB can be chamfered, but also ferrite
10. What is a square graph of the demagnetization curve?
The square graph of the demagnetization curve is an important magnetic characteristic index of a permanent magnet. When the magnet is under dynamic working conditions, the external reverse magnetic field H or the demagnetizing field Hd inside the magnet changes periodically. For Nd-Fe-B sintered magnets, the closer the B demagnetization curve is to a straight line, the magnet's The better the stability.
It is worth noting that if the B demagnetization curve of the magnet is not a straight line, the magnet's return permeability μrec. It has different values at different operating points, and it is very important how to design the magnet in the most stable working state at this time. Define the demagnetization curve of the magnet, the magnitude of the reverse magnetic field is Hk, Hk / Hcj can intuitively represent the squareness of the demagnetization curve of the magnet. For Nd-Fe-B sintered magnets with high Hcj, jHc is much larger than BHC. Hk / Hcj is also one of the important magnetic characteristic indexes of permanent magnets.
Custom Magnets If you need custom magnets, please kindly advise the following items:
a. Dimensions or drawing with tolerances.
b. Material grade or magnetic properties.
c. Quantity and delivery terms.
d. Surface coating (If necessary).
e. Magnetic direction.
Export manager: Bella Wong
Email: sales@robomagnetic.com
WhatsApp: +86 13586742171
If you need to know further information, please click here: https://www.robomagnetic.com
ROBO Magnetic is a professional manufacturer, supplier and OEM exporter of neodymium magnets(also referred to as NdFeB, NIB or Neo magnet)magnetic products.
