Neodymium ring magnets are usually made by drilling and machining hole on disc magnets and they also can be made a ring shape directly in pressing machines if order quantity is large enough to make a new tooling for it. For some bigger ring magnets we also have to mill the inner diameter and outer diameter in order to guarantee the suitable size before coating and finally they will be coated Nickel(Ni-Cu-Ni), Black Nickel, Zinc(Trivalent), Epoxy, Stannum, Gold, Silver or Parylene etc in order to keep from rusting. The highest grades for these products are N52, N48M, N44H, N42SH, N38UH and N35EH etc and the biggest size is about D220 X d80 x 50mm and this kind of Neodymium ring magnets are usually used in loudspeakers, mobile phones, DC motors and other electronic products and magnetic assemblies.

*Please Note: MJM Magnetics mainly produce Custom-made NdFeB magnets and magnetic assemblies with high quality at competitive prices, so if you are interested in the above products and looking for a reliable supplier who can produce this kind of products according to your special requirement, please Contact Us Now and we make sure we won't let you down if you could give us a chance to help!