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sales@tujinmagnet.com
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+86-18858010843
Rare Earth Countersunk Ring Magnet is a high-performance, high-strength magnet product. Made of rare earth materials, it has good magnetic properties and can meet the magnetic requirements in various complex environments. At the same time, its unique countersunk ring design enables it to perform well in various application scenarios. This magnet is in the shape of a ring with a countersunk hole in the center. This design not only increases the practicality of the magnet, but also makes its appearance more unique. The surface is smooth and silver, with no obvious flaws or scratches, showing a high-quality craftsmanship. The edges of the magnet are finely processed to present a rounded transition, avoiding damage to other objects or people during use. The design of the countersunk hole allows the magnet to be easily fixed or connected to other objects, increasing the breadth of its application scenarios.
Application scenarios
Automobile manufacturing
Engine component fixing: In automobile engines, this magnet can be used to fix various sensors, actuators and other components to ensure that they do not loosen or fall off during work.
Door and window components: It can also be used for magnetic fixing of components such as door handles and window lifters to improve the overall safety and convenience of the car.
Electronics and Communications
Speakers and Headphones: Rare earth magnets are one of the key components for producing sound in speakers and headphones. This countersunk ring magnet can be used to fix the speaker diaphragm or headphone driver unit to ensure clear and stable sound quality.
Sensors and Detectors: It can also be used in various sensors and detectors, such as magnetic sensors, position sensors, etc., to provide accurate signals and feedback for electronic devices and systems.
Products show

Surface Coating & Corrosoin Resistance
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| Nickel(Ni-Cu-Ni) | Zinc(Zn) | Black Epoxy | Gold |
| Type | Color | Plating Thickness | Working Temperature |
Advantage & Suitable | Salt Spray Resistance | |||||
| Nickel(NiCuNi) | silver | 20-30 um | ≤200 | high oxidation resistance, good glossiness, stable performance, long service life | > 72 hrs | |||||
| Zinc (Zn) | blue white | 10-20 um | ≤160 | suitable for low requirements for surface appearance & oxidation resistance | > 48 hrs | |||||
| Epoxy | black | 10-30 um | ≤120 | suitable for high anti-corrosion and strict atmospheric environment | > 96 hrs | |||||
| Gold | Gold | 5-30 um | ≤200 | suitable for decoration accessories, gift box etc. | > 24 hrs | |||||
Tolerance

| Standard Product | D.OD | ID | L | W | H |
| <5mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm |
| <10mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm |
| <20mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm |
| <50mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm | ±0.1mm |
| <100mm | ±0.15mm | ±0.15mm | ±0.15mm | ±0.15mm | ±0.15mm |
| >100mm | ±0.2mm | ±0.2mm | ±0.2mm | ±0.2mm | ±0.2mm |
Magnetization Direction
| Disc&Cylinder-through Thickness | Disc&Cylinder-through Diameter | Spheres- through Diameter |
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Poles on the flat surfaces
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Poles on the side surfaces |
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| Block- through Thickness | Block- through Length | Arc- through Diamter |
|
Poles on the larger flat surfaces |
Poles on the smaller flat surfaces |
Poles on outside&inside faces |
| Arc- through Length | Ring- through Surfaces | Ring- through Surfaces |
|
Poles on outside&inside faces |
Planar octupole magnetization |
Planar quadrupole magnetization |
Sintered NdFeB Magnetic Properties
| Grade | Remanence | Coercive Force | Intrinsic Coercivity | Maximum Energy | Working≤ | |||||||
| Br(KG) | Br(T) | Hcb (KOe) |
Hcb (KA/m) |
Hcj (KOe) |
Hcj (KA/m) |
(BH)max(MGOe) | (BH)max (KJ/ m) |
℃ | ||||
| Max | Min | Max | Min | |||||||||
| N35 | ≥11.8 | ≥1.18 | ≥10.8 | ≥860 | ≥12 | ≥960 | 37 | 33 | 295 | 263 | N | ≤80 |
| N38 | ≥12.3 | ≥1.23 | ≥10.8 | ≥860 | ≥12 | ≥960 | 39 | 36 | 310 | 287 | ||
| N40 | ≥12.7 | ≥1.27 | ≥11.0 | ≥876 | ≥12 | ≥960 | 41 | 38 | 327 | 302 | ||
| N42 | ≥13.0 | ≥1.30 | ≥11.0 | ≥876 | ≥12 | ≥960 | 43 | 40 | 343 | 320 | ||
| N45 | ≥13.3 | ≥1.33 | ≥11.0 | ≥876 | ≥12 | ≥960 | 46 | 42 | 366 | 335 | ||
| N48 | ≥13.7 | ≥1.37 | ≥10.5 | ≥836 | ≥12 | ≥960 | 49 | 45 | 390 | 358 | ||
| N50 | ≥14.0 | ≥1.40 | ≥10.5 | ≥836 | ≥12 | ≥960 | 51 | 47 | 406 | 374 | ||
| N52 | ≥14.2 | ≥1.42 | ≥10.5 | ≥836 | ≥12 | ≥960 | 53 | 49 | 422 | 390 | ||
| N54 | ≥14.4 | ≥1.44 | ≥10.5 | ≥836 | ≥11 | ≥876 | 55 | 51 | 438 | 406 | ||
| N35M | ≥11.8 | ≥1.18 | ≥10.8 | ≥860 | ≥14 | ≥1114 | 37 | 33 | 295 | 263 | M | ≤100 |
| N38M | ≥12.3 | ≥1.23 | ≥11.0 | ≥876 | ≥14 | ≥1114 | 39 | 36 | 310 | 287 | ||
| N40M | ≥12.7 | ≥1.27 | ≥11.5 | ≥915 | ≥14 | ≥1114 | 41 | 38 | 327 | 302 | ||
| N42M | ≥13.0 | ≥1.30 | ≥11.8 | ≥939 | ≥14 | ≥1114 | 43 | 40 | 343 | 320 | ||
| N45M | ≥13.3 | ≥1.33 | ≥12.0 | ≥956 | ≥14 | ≥1114 | 46 | 42 | 366 | 335 | ||
| N48M | ≥13.7 | ≥1.37 | ≥12.2 | ≥972 | ≥14 | ≥1114 | 49 | 45 | 390 | 358 | ||
| N50M | ≥14.0 | ≥1.40 | ≥12.5 | ≥995 | ≥14 | ≥1114 | 51 | 47 | 406 | 374 | ||
| N52M | ≥14.2 | ≥1.42 | ≥12.5 | ≥995 | ≥14 | ≥1114 | 53 | 49 | 422 | 390 | ||
| N33H | ≥11.4 | ≥1.14 | ≥10.6 | ≥844 | ≥17 | ≥1350 | 35 | 31 | 279 | 247 | H | ≤120 |
| N35H | ≥11.8 | ≥1.18 | ≥10.8 | ≥860 | ≥17 | ≥1350 | 37 | 33 | 295 | 263 | ||
| N38H | ≥12.3 | ≥1.23 | ≥11.0 | ≥876 | ≥17 | ≥1350 | 39 | 36 | 310 | 287 | ||
| N40H | ≥12.7 | ≥1.27 | ≥11.5 | ≥916 | ≥17 | ≥1350 | 41 | 38 | 327 | 302 | ||
| N42H | ≥13.0 | ≥1.30 | ≥11.8 | ≥940 | ≥17 | ≥1350 | 43 | 40 | 343 | 320 | ||
| N45H | ≥13.3 | ≥1.33 | ≥12.0 | ≥955 | ≥17 | ≥1350 | 46 | 42 | 366 | 335 | ||
| N48H | ≥13.6 | ≥1.36 | ≥12.2 | ≥971 | ≥17 | ≥1350 | 49 | 45 | 390 | 358 | ||
| N50H | ≥14 | ≥1.4 | ≥12.5 | ≥995 | ≥17 | ≥1350 | 51 | 47 | 406 | 374 | ||
| N52H | ≥14.3 | ≥1.43 | ≥12.5 | ≥995 | ≥17 | ≥1350 | 53 | 49 | 422 | 390 | ||
| N33SH | ≥11.4 | ≥1.14 | ≥10.6 | ≥844 | ≥20 | ≥1592 | 35 | 31 | 279 | 247 | SH | ≤150 |
| N35SH | ≥11.8 | ≥1.18 | ≥10.8 | ≥860 | ≥20 | ≥1592 | 37 | 33 | 295 | 263 | ||
| N38SH | ≥12.3 | ≥1.23 | ≥11.0 | ≥876 | ≥20 | ≥1592 | 39 | 36 | 310 | 287 | ||
| N40SH | ≥12.6 | ≥1.26 | ≥11.5 | ≥916 | ≥20 | ≥1592 | 41 | 38 | 327 | 302 | ||
| N42SH | ≥12.9 | ≥1.29 | ≥11.8 | ≥940 | ≥20 | ≥1592 | 43 | 40 | 343 | 320 | ||
| N45SH | ≥13.2 | ≥1.32 | ≥12.0 | ≥955 | ≥20 | ≥1592 | 46 | 42 | 366 | 335 | ||
| N48SH | ≥13.6 | ≥1.36 | ≥12.2 | ≥971 | ≥20 | ≥1592 | 49 | 45 | 390 | 358 | ||
| N50SH | ≥14 | ≥1.4 | ≥12.5 | ≥995 | ≥20 | ≥1592 | 51 | 47 | 406 | 374 | ||
| N33UH | ≥11.4 | ≥1.14 | ≥10.6 | ≥844 | ≥25 | ≥1990 | 35 | 31 | 279 | 247 | UH | ≤180 |
| N35UH | ≥11.8 | ≥1.18 | ≥10.8 | ≥860 | ≥25 | ≥1990 | 37 | 33 | 295 | 263 | ||
| N38UH | ≥12.3 | ≥1.23 | ≥11.0 | ≥876 | ≥25 | ≥1990 | 39 | 36 | 310 | 287 | ||
| N40UH | ≥12.6 | ≥1.26 | ≥11.5 | ≥916 | ≥25 | ≥1990 | 41 | 38 | 327 | 302 | ||
| N42UH | ≥12.9 | ≥1.29 | ≥11.8 | ≥940 | ≥25 | ≥1990 | 43 | 40 | 343 | 320 | ||
| N45UH | ≥13.2 | ≥1.32 | ≥12.0 | ≥955 | ≥25 | ≥1990 | 46 | 42 | 366 | 335 | ||
| N48UH | ≥13.6 | ≥1.36 | ≥12.2 | ≥971 | ≥25 | ≥1990 | 49 | 45 | 390 | 358 | ||
| N28EH | ≥10.4 | ≥1.04 | ≥9.50 | ≥756 | ≥30 | ≥2388 | 30 | 26 | 239 | 207 | EH | ≤200 |
| N30EH | ≥10.8 | ≥1.08 | ≥9.50 | ≥756 | ≥30 | ≥2388 | 32 | 28 | 255 | 223 | ||
| N33EH | ≥11.4 | ≥1.14 | ≥10.6 | ≥844 | ≥30 | ≥2388 | 35 | 31 | 279 | 247 | ||
| N35EH | ≥11.8 | ≥1.18 | ≥10.8 | ≥860 | ≥30 | ≥2388 | 37 | 33 | 295 | 263 | ||
| N38EH | ≥12.3 | ≥1.23 | ≥11.0 | ≥876 | ≥30 | ≥2388 | 39 | 36 | 310 | 287 | ||
| N40EH | ≥12.6 | ≥1.26 | ≥11.5 | ≥916 | ≥30 | ≥2388 | 41 | 38 | 327 | 302 | ||
| N42EH | ≥12.9 | ≥1.29 | ≥11.8 | ≥940 | ≥30 | ≥2388 | 43 | 41 | 343 | 320 | ||
| N45EH | ≥13.2 | ≥1.32 | ≥12.0 | ≥955 | ≥30 | ≥2388 | 46 | 42 | 366 | 335 | ||
| N30TH | ≥10.8 | ≥1.08 | ≥9.50 | ≥756 | ≥35 | ≥2786 | 32 | 28 | 255 | 223 | TH | ≤220 |
| N33TH | ≥11.4 | ≥1.14 | ≥10.6 | ≥844 | ≥35 | ≥2786 | 35 | 31 | 279 | 247 | ||
| N35TH | ≥11.8 | ≥1.18 | ≥11.0 | ≥876 | ≥35 | ≥2786 | 37 | 33 | 295 | 263 | ||
| N38TH | ≥12.2 | ≥1.22 | ≥11.0 | ≥876 | ≥33 | ≥2627 | 39 | 36 | 310 | 287 | ||
| Remarks: The maximum working temperature depends on the shape, size, and coating of the magnet, the highest working temperature in the table is the test data for standard sample. | ||||||||||||
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