As the third generation of rare earth permanent magnet, Neodymium magnets are the most powerful commercially produced magnets. Neodymium arc magnet, also known as Neodymium curved magnet, is a unique shape of sintered Neodymium magnet, then almost all of Neodymium arc magnet is used for both rotor and stator in permanent magnet (PM) motors, generators, or magnetic coupling devices.
SDM Magnetics Co., Ltd.
SDM Magnetics - Neodymium Arc Magnet for Motors and Generators
Neodymium arc magnets, a subtype of sintered Neodymium magnets, are vital components in the manufacture of permanent magnet motors, generators, and magnetic coupling devices. As powerful rare earth magnets, they are primarily used for rotor and stator applications, where their distinct curved shape is integral to efficient electromagnetic operation. Machining these magnets involves techniques like wire-cutting and copy grinding, both having distinct advantages and limitations in terms of efficiency and cost. The magnets are often radially or axially magnetized for use in specific motor configurations like radial flux and axial flux motors. For enhanced performance, such as reducing eddy current losses and improving magnetic field distribution, laminated arc magnets or Halbach arrays may be implemented. These advancements can mitigate cogging torque and optimize motor operation despite the technical challenges in manufacturing.Most popular related searches
Due to technical limitations in the magnetic field orientation molding process, Neodymium arc magnet is always machined from blank. Machining process of curved magnet is normally selected from wire-cutting or copy grinding. Wire-cutting is well adapted to the machining of special shaped magnet, but it also accused of low production efficiency and high processing cost. On the contrary, copy grinding has the competitive advantage in efficiency and cost but short in dimensional applicability. Magnet manufacturers should utilize appropriate machining technology in accordance to the shape, dimension, material utilization ratio, production efficiency, and processing cost.
Neodymium arc magnet for frequently-used radial flux motor is magnetized through diametrical direction and definitely used in pairs. It should be noted that pure radially magnetized Neodymium arc magnets are extremely difficult to manufacture. Fan-shaped arc magnet is commonly served as axial flux motor magnet. For some axial flux motor, a certain quantity of chord magnetized magnet should be placed between regular axially magnetized magnet to form a Halbach array, then obtain more ideal magnetic field strength and distribution.
The vast majority of Neodymium arc magnet serve as motor magnet. Besides magnetic performance and surface protective treatment, both shape and structure of the magnet have significantly impacts on the motor performance. It is a challenge for slotted motor to avoid cogging torque caused by interaction between the magnet and the stator tooth. In order to suppress torque ripple, vibration, and noise generated by cogging torque, curved magnet in either frequently-used radial flux motor or axial flux motor can be modified into the skewed shape. Eddy current is generally leading the temperature rise in the permanent magnet and caused demagnetization. Hence decreased the working efficiency of the motor. Laminated arc magnet which made by bonding several pieced of thin magnet together can dramatically reduce the eddy current loss without replacing the original structure and performance of the motor.