Advantages and Disadvantages of Ring Magnets for Electric Motors

Advantages and Disadvantages of Ring Magnets in Motors

Ring magnets used in motors are typically sintered ferrite magnets or injection-molded ferrite magnets. The disadvantage is that both materials have relatively poor magnetic properties. The advantages include low cost, ease of assembly, and the fact that at typical rotational speeds like 5000 rpm, no protective measures are needed around the magnets. However, this is sufficient for most standard motors.

Ring-shaped sintered neodymium-iron-boron magnets, including bonded types, require specialized molds for both production and magnetization, resulting in higher costs. Magnetization methods are diverse, enabling the creation of superior sinusoidal magnetic fields. In high-speed motor applications, they offer greater reliability than conventional options.

What are the advantages and disadvantages of ring-shaped sintered NIBO magnets?

Advantages: Simple structure, easy installation, and reduced assembly costs.

Disadvantages: Higher cost compared to tile designs.

Technologically, the radiation ring design is highly mature, with major domestic and international clients already using it in bulk production.

Generally, what size magnets can be magnetized into how many poles? Like 4-pole or 8-pole configurations.

Currently, the smallest diameter is 14mm, while the largest is around 70mm (larger sizes are feasible but unproduced). The aspect ratio and wall thickness are critical factors directly impacting yield rates and mass production feasibility. Specific specifications require individual analysis.

How effective is the magnetization process?

If making magnetic rings is like baking a cake, magnetization and polarization are the slicing process. Theoretically, there are few limitations—you can slice it into as many pieces as needed.