Diametrical magnetization is most commonly used in magnets with a circular profile, especially cylindrical magnets and ring magnets. In these shapes, the diameter provides a clear reference for defining the pole orientation, making diametrical magnetization easier to describe and more practical to apply.
Cylindrical magnets are one of the most typical forms for this magnetization pattern. With the poles arranged across the diameter, they are often selected for assemblies where the magnetic field needs to be distributed around the outside of the part rather than from one flat end to the other.
Ring magnets are also commonly made with diametrical magnetization. In these cases, the magnetic field pattern is defined across the diameter of the ring, which makes this shape suitable for round assemblies that require a magnetic field around the side of the magnet.
In some cases, arc magnets may also be described with a similar magnetization direction depending on the geometry and application.
Diametrically magnetized magnets are sometimes confused with radially magnetized magnets because both terms are used to describe non-axial magnetization in cylindrical or ring-shaped parts. However, they refer to different ways in which the magnetization direction is distributed.
Diametrical magnetization follows one fixed direction across the magnet. Radial magnetization changes around the circumference, following the local radial direction at each position. As a result, diametrically magnetized rings have poles on opposite sides, while radially magnetized rings have opposite polarities on their inner and outer diameter surfaces.
Diametrically magnetized magnets and diametrically multipole magnetized magnets should not be understood as the same magnetization pattern. In a standard diametrically magnetized magnet, the magnetic poles are arranged as one North pole and one South pole across the diameter. This is the form most commonly associated with cylindrical magnets and ring magnets used in simple structures.
By contrast, diametrically multipole magnetized magnets have more than two alternating poles arranged around the ring. For this reason, diametrically multipole magnetized magnets are usually discussed as multipole ring magnets rather than as standard diametrically magnetized magnets.
Although both belong to side-oriented magnetization patterns in ring-shaped parts, their magnetic field distribution, magnetizing fixture design, and typical applications are clearly different. Standard diametrical magnetization is generally used when a single pole pair across the diameter is required, while diametrical multipole magnetization is used when multiple pole pairs are needed around the ring.
Diametrically magnetized magnets can be produced in different permanent magnet materials, but in practice the material choice is usually linked closely to magnet shape, size, magnetic output, and the requirements of the final assembly.
Neodymium (NdFeB) magnets are commonly used for diametrically magnetized cylindrical and ring magnets when stronger magnetic output is needed in a limited space. This is often the preferred choice for compact designs where stronger magnetic output is required within a relatively small diameter.
Ferrite magnets are also widely used for diametrically magnetized parts, especially for ring and cylindrical shapes in cost-sensitive applications. Although their magnetic output is lower, they remain a practical option when the design allows a larger size or when material cost is a more important consideration.
Samarium Cobalt (SmCo) magnets may also be used for diametrically magnetized magnets when better temperature stability or environmental resistance is required. Compared with Neodymium and ferrite magnets, this material is more often chosen for specific working conditions rather than for general-purpose designs.
In actual projects, the material is usually selected together with the part geometry, magnetization pattern, and the performance required in the final assembly.
When requesting diametrically magnetized magnets, it is important to describe not only the magnet shape and dimensions, but also the required magnetization direction in relation to the part geometry. For cylindrical and ring magnets, this usually means confirming that the poles are arranged across the diameter rather than through the thickness or along the axis.
In actual projects, the specification normally includes the magnet material, part size, dimensional tolerance, magnetization pattern, coating requirement if needed, and the application requirements of the final assembly. If the magnet is intended for a rotating structure, shaft assembly, or sensor-related design, it is also helpful to provide the installation method and the expected magnetic performance.
For custom parts, drawings or reference sketches are often useful for avoiding confusion, especially when the magnet shape is simple but the required pole orientation is critical. In many cases, the correct specification of the magnetization direction is just as important as the material and dimensions, since it directly affects how the magnet will perform in the final product.
