3 Commonly Used Types of Neodymium Magnets

Neodymium magnet, is currently the strongest magnetic permanent magnet, according to the different manufacturing processes are mainly divided into sintered neodymium magnets, bonded neodymium magnets, injection molded neodymium magnets, which have many different magnetic properties, appearance, and application areas.

Sintered neodymium(ndfeb) magnets

Sintered neodymium magnets are the most common and used type of permanent magnets, which are made by mixing the powder of neodymium, iron and boron, pressed and molded and then sintered at high temperature, and then finally processed by slicing, punching and wire cutting to get the shapes and sizes required by customers.

Main features of sintered neodymium magnets;

Very high magnetic energy product (BHmax), usually between 35 and 54 MGOe.

Easy to process all kinds of common or special shapes (small, thin are no problem).

Good mechanical properties, brittle and fragile.

Good corrosion resistance with surface added plating.

Good temperature stability, can maintain high magnetic properties in a wide temperature range.

Application areas: super wide, basically need to provide magnetic products can use it, we use every day cell phone, headphones have its existence.

Bonded neodymium magnets

Bonded neodymium magnets are made by mixing NdFeB magnetic powder with binder, and then pressed and shaped through molds. Since sintering is not required, the manufacturing process is relatively simple and the cost is relatively low, and is generally based on multi-pole magnetization.

Bonded neodymium magnet appearance picture, black coating.

Main characteristics of bonded neodymium magnets;

Moderate magnetic properties, lower than sintered Nd magnets, typically between 10 and 16 MGOe.

Easily integrated and molded, suitable for miniaturized applications.

Various magnetization methods, including inner circle multi-pole magnetization, outer circle multi-pole magnetization, plane multi-pole magnetization, bevel or spiral magnetization.

Can be combined with shafts, housings, plastic gears and other plastic parts or hardware through injection molding, adhesive, etc. to form assemblies, which are convenient for customers' applications.

Typical applications: Various micro and small motors, such as spindle motors, stepper motors, synchronous motors, DC motors, brushless DC motors, and also widely used in various types of sensor devices. 

Injection Molded Neodymium Magnets

Injection molded neodymium magnets are made by mixing neodymium magnetic powder with thermoplastic, and then made by injection molding process. This process allows for the incorporation of complex functional structures during the manufacturing process, with the main radial multi-pole magnetization as the main focus, and can be molded as one piece of injection molding with other metal parts.

Main features of injection molded NdFeB;

It is possible to produce magnets of various complex shapes and detailed sizes, and even magnets with embedded metal or other parts can be molded in one shot.

Excellent corrosion resistance, no plating required on the surface.

Better impact resistance and durability, not fragile.

Due to the inclusion of a plastic matrix, injection molded neodymium magnets have a lower density and a lighter overall mass

By adjusting the content, grade of NdFeB magnetic powder, you can adjust the magnet's high or low magnetic performance.

Main applications: Suitable for applications with complex shapes and high mechanical strength requirements, such as micro motors, electronic equipment, sensors and medical devices.

In terms of selection, if the requirements for high magnetic properties, it is recommended to use sintered NdFeB. For moderate magnetic strength requirements, need multi-pole magnetization, choose bonded neodymium magnets. For complex shape requirements, not fragile, not so high magnetic properties, you can choose injection molding neodymium magnets.

Related magnet products;

Plastic bonded neodymium magnets

Help file:

Bonded vs Sintered Neodymium Magnets

Difference between bonded NdFeB and injection molded ferrite magnet