What type of magnetic material do they use in cordless drill motors?
(I’m doing some research on the design of cordless drill motors. I’m familiar with the electrical design aspects of permanent magnet DC motors, but I’m having trouble finding actual specifications for the typical magnetic material used for this particular application.)
Run of the mill magnets can be made from a piece of steel shaped to fit.
High-quality, fancy-shaped magnets are these days often made from powdered iron (sometimes mixed with other metals) and cast into the right shape.
Here’s a little tech talk.
I’m well aware of magnetic technology.
I’m looking for the specific implementation found in cordless drill motors. Alnicos 1 - 9? Ferrites? etc. I don’t have a spare motor laying around that I can take apart…
Bump bump bump. C’mon all you smart dopers…CrafterMan? Chronos? Q.E.D.?
The manufacturers do seem a little reticent about describing their motor designs.
Hitachi goes so far as to say: 2-piece rare-earth magnet motor for greater durability and increased performance, the others stick to “high grade field magnets.”; not much help.
This article on MOTOR DESIGN: Models, Methods and Motion, at least made the digging a little interesting.