Laminated magnet Anti eddy current permanent magnet is a special magnetic component, also known as insulation magnet or glue magnet, English name: laminated magnet. Because it consists of several individual thin rare-earth permanent magnets bonded to each other by an insulating glue. Rare earth magnets, for example, are glued together or glued to steel plates of the same polarity. Anti-eddy current permanent magnet can reduce eddy current loss in high power motor and improve motor performance. The smaller the eddy current loss, the less heat and waste, thus preventing the magnet from overheating and losing its magnetism. Laminated samarium-cobalt permanent magnets or laminated Ndfeb magnets bonded with insulating glue have been shown to significantly reduce eddy current losses in high-efficiency motors. This means that the resistance between bonded magnets may be 102 to 104 times greater than that of conventional sintered magnets due to the insulating adhesive. Therefore, anti-eddy current permanent laminated magnets are an ideal solution to improve motor efficiency and are widely used in aerospace, automotive sports, automotive and other fields.
Magnetic source magnetic products can provide samarium cobalt and Ndfeb anti-vortex magnets:
1, Ndfeb has a variety of properties, magnetic energy product from 30MGOe (230KA/m3) to 55MGOe, working temperature from room temperature to 280°C, can be used for a variety of types and uses of motor. High Hcj anti - eddy dymium magnets are widely used in new energy motor, aerospace and other fields.
2. Magnetic NdFeb anti-eddy current laminate is a very ideal magnetic material in the need of stable magnetic field or working environment in corrosive environment. Because of its excellent thermal stability, α (Br) as low as -0.03%/ºC and β (Hcj) as low as -0.2%/ºE, as well as excellent corrosion resistance without surface treatment.
The advantages of anti-eddy current permanent magnet body:
1.outer coating epoxy, can be used to protect Ndfeb magnets from rust, for samarium cobalt magnets, can reduce the risk of magnet Angle.
2.working temperature up to 200℃;
3.the unique layer bonding insulation method increases the working efficiency of the motor, its machinable characteristics ensure the manufacturing accuracy, has a little competitive advantage in cost control;
5.The magnets are insulated from each other, which can prevent the heat generated by large eddy current;
6.insulation layer thickness is 0.025mm-0.10mm (25um-100um);
7.magnetic materials can be samarium cobalt or Ndfeb;
8.magnet shape can be divided into blocks, segments or wedges;
9.by reducing electromagnetic eddy current loss, avoid irreversible demagnetization, improve the safety and stability of motor work.
Disadvantages of anti-eddy current magnet:
1.Due to the limit of the maximum working temperature of glue, the maximum working temperature shall not exceed 200℃;
2.the production mode is complex, the delivery time is long, the unit cost is higher than the ordinary magnet;
3.Anti-eddy NdFeb magnets are easy to rust, and need to be coated with protective coating, but they can only be coated with epoxy or paint after viscose, not NiCuNi or Zn coating. Eddy-proof samarium cobalt permanent magnets do not require a protective coating but are prone to Angle loss.
Why are anti-vortex magnets expensive?
1.Samarium magnets and neodymium magnets are not cheap. In particular, the price of neodymium 2021 has more than tripled.
2. To achieve good bonding force, high grade insulation and high temperature resistance, high quality glue is not cheap.
3. Anti-eddy current magnets are not simply glued together by thin parts as one might see, and many factors must be considered in the manufacturing process. Because the tolerances of the finished magnets are very strict, we have to use larger size magnets for bonding, and the magnets have to be cut into thin slices before bonding. After bonding, it is processed according to different shapes and sizes. Therefore, the expensive samarium cobalt and neodymium magnet materials, as well as the more complex processing processes, mean that their costs are much higher than those of ordinary samarium cobalt or NdFeb magnets.
Application of flow magnet
The anti-eddy current magnet is mainly used in servo motors, traction motors, linear motors and elevator motors, etc., because it can reduce the eddy current loss of efficient motors by insulating each magnet. The smaller the eddy current loss, the lower the heat of the motor, the higher the efficiency.