China Neodymium And Ferrite Magnets Manufacturer & Supplier 
Cylinder magnet with hole are a common type of magnet shape, created by drilling holes into cylindrical magnets. The holes serve multiple purposes, including facilitating screw fixation, bearing insertion, or mechanical assembly, as well as meeting specific installation requirements for certain applications. The following sections will provide an overview of the primary materials used in hollow cylindrical magnets and their common shape types.
Image of a cylindrical neodymium magnet with holes
First, in terms of material, the main type of perforated cylindrical magnets currently available are made primarily from neodymium, as it possesses extremely high remanence and coercivity, resulting in compact size and strong magnetic force. The holes can be either screw holes (countersink holes) or through holes (straight holes), and are widely used in motors, sensors, magnetic connection devices, industrial applications, medical devices, and social security systems. In addition to neodymium, ceramic ferrite is also widely used, with holes primarily being straight holes. These are commonly found in water pump motor rotors, small appliances, and instruments. As for samarium cobalt, due to its poor cost-effectiveness, it is only selected for environments where temperatures exceed 200°C. Generally, it is replaced by neodymium.
Common types of cylindrical magnets with holes and hole locations
There are primarily two types of holes based on their shapes: counterbore (countersunk hole) and round hole. Round holes are the most common and can accommodate shafts, such as motor shafts. The upper end of a counterbore hole is flared (conical), making it suitable for countersunk screw fixation.
Looking at the position of the holes, the holes in cylindrical magnets are mainly located in the center (most common), and some are designed on the side, such as the sample Strong cylindrical magnet with one side hole n52.
In terms of magnetization, most cylindrical magnets with through holes are radially magnetized, such as radially 2-pole and radially 4-pole magnets. Cylindrical magnets with countersunk holes are mostly magnetized axially (axial magnetization).
The above is an overview of the primary materials and types of perforated cylindrical magnets. These magnets have widespread applications across various industries, including industrial, household, electronic, and medical fields. Currently, over 90% of our customers opt for neodymium material. If you require a quote or customization, please feel free to contact us.
Classic samples;
20mm x 20mm x 6mm Hole Rare Earth Screw Hole Magnet Cylinder
10mm x 4mm x 15mm hollow cylinder ferrite rotor radial 4 poles