Differences between sintered and bonded neodymium magnets

Distinguish between Bonded NdFeB Magnets and Sintered NdFeB Magnet from appearance

Texture: Bonded NdFeB magnets typically have a smoother surface texture than sintered NdFeB magnets. This is because the binder material used in the manufacturing process of bonded magnets fills in the gaps between the magnetic particles, resulting in a smoother surface.

Color: Sintered NdFeB magnets are usually darker in color compared to bonded NdFeB magnets, which can be lighter in color.

Shape and Size: Bonded NdFeB magnets can be manufactured in complex shapes and sizes, while sintered NdFeB magnets are usually limited to simpler shapes due to the manufacturing process. Therefore, if the magnet is an unusual shape or size, it is more likely to be a bonded NdFeB magnet.

Density: Sintered NdFeB magnets are denser than bonded NdFeB magnets. You can test the density by weighing the magnet and comparing it to the weight of a known sintered NdFeB magnet of the same size.

Magnetization direction: The magnetization direction of sintered NdFeB magnets is typically marked on the magnet itself, while bonded NdFeB magnets may not have any markings.

Differences between sintered and bonded neodymium magnets:

Magnetic properties: Sintered neodymium magnets have higher magnetic energy products than bonded neodymium magnets. Sintered NdFeB magnets may have a maximum energy product (BHmax) of up to 56 MGOe(It changes based on NdFeB magnet grade), while bonded NdFeB magnets have a maximum energy product of around 8-25 MGOe. This means that sintered NdFeB magnets have a higher magnetic strength and can be used in applications that require a strong magnetic field. This means they can generate stronger magnetic fields and are better suited for applications that require high magnetic strength, such as in electric motors and generators.

Manufacturing process: Sintered neodymium magnets are made by compressing neodymium powder in a magnetic field and then sintering it at high temperatures. This process results in a dense and uniform structure with high magnetic properties. This process results in a dense, high-strength magnet with excellent magnetic properties. Bonded neodymium magnets, on the other hand, are made by mixing neodymium powder with a polymer binder and then pressing it into a mold. This process is less expensive and can be used to create complex shapes and sizes. This process results in a magnet with lower magnetic properties and a less dense structure.

Cost: Sintered neodymium magnets are generally more expensive than bonded neodymium magnets due to the higher production costs associated with their manufacturing process and the raw materials used. This is because the manufacturing process for bonded NdFeB magnets is less complex and requires fewer steps than the process for sintered NdFeB magnets. Bonded NdFeB magnets are also easier to shape and can be produced in larger quantities, which helps to reduce costs.

Temperature stability: Sintered neodymium magnets have higher resistance to demagnetization at high temperatures compared to bonded neodymium magnets. This makes them suitable for high-temperature applications, such as in electric motors, while bonded magnets are more suitable for applications at lower temperatures.

Sintered NdFeB magnets have better temperature stability than bonded NdFeB magnets. Some Sintered NdFeB magnets can operate at temperatures up to 200°C without significant loss of magnetic properties. Zhongke NTH series(N28TH,N30TH,N33TH,N35TH,N38TH,N40TH,N42TH) sinter ndfeb magnet Maximum Working Temperature Tw L/D = 0.7 archives 220°c.

Bonded NdFeB magnets, on the other hand, can begin to lose their magnetic properties at temperatures above 120°C. This makes sintered NdFeB magnets more suitable for high-temperature applications.

Durability: Regarding the durability of sintered NdFeB magnets being higher than that of bonded NdFeB magnets may not be entirely accurate.

While sintered NdFeB magnets do have a denser structure and may be less prone to cracking or breaking under stress than bonded NdFeB magnets, both types of magnets can be quite durable when used properly in appropriate applications.

Factors such as the size, shape, and strength of the magnet, as well as the specific application in which it is used, can all affect the durability of a magnet. In some cases, bonded NdFeB magnets may actually be more durable than sintered NdFeB magnets.