much less efficient either for bonded or sintered, either isotropic or anisotropic Neo ring magnets, a fixture is hard to apply a high field to saturate such magnets. It is very common though to make Alnico solid one-piece ring magnets with either multiple poles, or radial oriented, or even with one inside pole, one outside pole, you name it.
Based on your latest post, you are looking for a full radially oriented NdFeB magnet. Very few suppliers keep these as standard items. If you only need a few, you will find it difficult to obtain. If you are looking for thousands, then a supplier might be willing to develop a tool
Janeriksen,
Maybe you need to step back and look at your proposed magnet and its pole pieces and see how you could do this with an axially oriented magnet and different pole pieces.
This geometry is difficult in RE materials (where powder must be oriented in the compaction tooling) and usually results in much lower properties.
In materials that develop orientation in heat treatment such as Alnico you can create a wide range of orientations (such as 6 pole rings).
I should have added that we used to build these out of magnet segments in RE materials.
The pieces were ground and epoxied together, not as mechanically strong as a single piece, but full magnetic properties.
The grade of Neodymium Iron Boron is not so important. It just has to be one outside and one inside pole, but I´ve understood now that this will be very hard to obtain and therefore also very expensive, so maybe I should give this up and instead try to glue smaller disc magnets together inside a thin metal ring and create one that way.
