Alignment Technique for Anisotropic Injection Magnets


The Alignment Technique for Anisotropic Injection Magnets refers to a specific method used in the manufacturing process of anisotropic injection-molded magnets to achieve the desired magnetic alignment or orientation within the final magnet product. Anisotropic injection magnets are a type of permanent magnet known for having a preferred direction of magnetization, which makes them particularly useful in applications where a specific magnetic field orientation is required.

Key Steps in the Alignment Technique:

Material Selection: The process begins by selecting suitable magnetic materials, which often include a mixture of magnetic powders (such as rare-earth elements) and a binder material (usually a polymer or resin). These materials are chosen to achieve the desired magnetic properties.

Magnetic Particle Alignment: To impart anisotropy to the magnet, the magnetic particles are initially randomly oriented within the binder material. Achieving alignment is critical for optimizing magnetic performance.

Application of Magnetic Field: An external magnetic field is applied to the mixture. This field helps align the magnetic particles in a preferred direction, corresponding to the desired orientation of the final magnet.

Injection Molding: The aligned mixture is then injected into molds that have the desired shape and dimensions for the final magnet product. The injection molding process helps maintain the alignment achieved in the previous step.

Curing or Solidification: After injection molding, the polymer or resin is cured or solidified, which locks the aligned magnetic particles in place, forming a permanent anisotropic magnet.

Alignment Technique for Anisotropic Injection Magnets

Importance of Alignment:

The alignment of magnetic particles is critical because it directly affects the magnetic properties of the anisotropic injection magnet. Proper alignment ensures that the magnet exhibits strong magnetic characteristics along the preferred axis while minimizing magnetic strength in other directions. This is especially important in applications where precise control of magnetic fields is required.


Anisotropic injection magnets with well-aligned magnetic domains find use in various industries and technologies, including:

Electric motors and generators
Sensors and actuators
Magnetic couplings
Magnetic assemblies
Magnetic resonance imaging (MRI) systems
Aerospace and automotive components

Quality Control:

To ensure the effectiveness of the Alignment Technique for Anisotropic Injection Magnets, quality control measures, including magnetic testing and inspection, are often employed during and after the manufacturing process to verify that the magnets meet the specified magnetic performance criteria.

What’s the difference between the isotropic magnet and anisotropic magnet?
Isotropic magnet’s crystal grains do not have their easy magnetization direction lined up in a specific direction and whose magnetic characteristic is isotropic. On the other hand, a magnet whose crystal grain directions are aligned and have their easy magnetization direction lined up is called an anisotropic magnet. Isotropic magnet includes bonded magnet using melt-spun powders as the raw material and isotropic ferrite magnets, but their magnetic properties are inferior to those of anisotropic magnets. The isotropic magnet can be magnetized form any direction.

What’s the different between the isotropic magnet and anisotropic magnet during manufacturing process?
Unlike isotropic magnet, the anisotropic magnet must apply alignment field during its manufacturing process, then most of the magnetic domains will aligned in the same direction to deliver maximum magnetic output. This alignment field process called orientation technology.

What are the two ways of orientation technology for anisotropic injection magnet?
The orientation technology for anisotropic injection magnet includes permanent magnet orientation and electromagnetic orientation.

The sketches of electromagnetic orientation technology
According to magnet’s shape and final magnetization direction, the aligning direction of electromagnetic orientation technology includes axial-orientation and radial-orientation. Japanese injection magnet manufacturers have several years of experience in this area.

The sketches of permanent magnet orientation technology
The technical difficulty of the permanent magnet orientation is less than the electromagnetic orientation technology. The sintered NdFeB or SmCo magnets are embedded in the mold to generate magnetic field. The strength of magnetic field is affected by many factors. Engineers design it based on the experience and Finite element method.

In summary, the Alignment Technique for Anisotropic Injection Magnets is a critical manufacturing method used to achieve the desired magnetic alignment in anisotropic injection-molded magnets. This alignment ensures that the magnets exhibit strong magnetic properties along specific axes, making them valuable in a wide range of industrial and technological applications.

Bonded Neodymium Anisotropic Injection Molding Magnets

Injection Molding Bonded BLDC Motor Magnets

Injection Molding Bonded Flow Sensor Magnets

Plastic Nylon Injection Molding Bonded SmCo

Club Car IQ High Speed ADC Motor Injection Molding Magnet

Permanent Magnet for Electronic Expansion Valve (EEV)