Permanent Sintered Neodymium /NdFeB Ring Magnets

Neodymium Ring Magnets are composed of Neodymium, Iron and Boron. Density of Neodymium magnets is. 27Lb/in3 (7.5g/cm3).
Neodymium Ring Magnets are manufactured in a metallurgy process through alloying, crushing, powdering, pressing w/magnetic orientation, sintering, then cutting, coating, inspecting and packing before shipment.
Neodymium Ring Magnets offer the highest (BH)max and high Hci(BH)max, the Maximum Energy Product, of Neodymium magnets is highest of any kind of permanent magnets today in the world. (BH)max at different grades of Neodymium magnets is 27 to 52 MGOe. Neodymium magnets have extremely resistance to demagnetization with Hci, Intrisic coercive force, over 12, 000 Oe. Because of very high (BH)max and Hci, Neo magnets could be used as a reversible medium for large amount of energy transformation in miniaturized application where a strong magnetic demagnetization field exists, such as computer hard drive. Disk and rectangle shapes for customers' immediate needs and accept special orders for custom Neodymium magnets.
Neodymium Ring Magnets are most powerful of any kind of magnetic materialsBr of Neodymium magnets are much more than 11, 000 Gauss. Therefore, Neodymium magnets have strong holding strength on metal surface and could be used as component for holding, separating, etc. Neodymium magnets must be carefully handled to avoid personal injury and material damage due to its extremely magnetic strength and brittle property.
Neodymium iron Boron are sensitive to temperature change and even lose magnet properties at high temperatureNeodymium magnets lose -0.09 ~ -0.13% of Br/° C and can work stably under 80° C for low Hci Neodymium magnets and 150° C for high Hci Neodymium magnets.
Neodymium magnets are corrupted in humid environment Surface protection is strongly recommended, such as plating, varnishing and encapsulating.
Neodymium iron Boron magnets are hard and brittle Neodymium magnets can be abrasively machined with coolant served to absorb heating and dust. Without coolant, rare earth magnets could crack and chip by the heat produced during high speed cutting or grinding, and the sparks contain the easily oxidized grinding dust that could cause fire!
Grades of Ring Magnets
N35-N52 (working temperature Max. 80)
33M-48M (working temperature Max. 100)
30H-45H (working temperature Max. 120)
30SH-42SH (working temperature Max. 150)
30UH-35UH (working temperature Max. 180)
28EH-35EH(working temperature Max. 200)
Dimension Range, Size and Tolerance
Ring Magnet Outer Radius*Inner Radius*Thickness*
Maximum150.0 mm95.0 mm50.0 mm
Minimum0.8 mm0.15 mm0.2 mm
Disc Neodymium Magnet Diameter*Thickness*
Maximum150.0 mm75.0 mm
Minimum0.4 mm0.25 mm
Block Neodymium Magnet Length*Width*Thickness*Diagonal*
Maximum200.0 mm95.0 mm50.0 mm150.0 mm
Minimum3.080 mm1.20 mm0.25 mm0.50 mm
Arc-segment Neodymium Magnet Outer Radius*Inner Radius*Thickness*Degree*
Maximum75 mm65 mm50.00 mm150
Minimum1.9 mm