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Physics/Using a permanent magnet as an electromagnet core

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Hello Mr Johnson,

Thank you very much for volunteering on this site - it is much appreciated by all people trying to educate themselves!
I am interested in the use of a permanent magnet as an electromagnet core. I have researched online but as yet have been unable to confirm my understanding and would much appreciate your comment.
I recently read online that A permanent magnet is made of ferromagnetic material, which is magnetised by a strong external magnetic field. The magnetically hard material that is used keeps part of its magnetisation after the external magnetic field is turned off. http://www.supermagnete.de/eng/faq/What-is-the-difference-between-a-permanent-ma
Based on the above quote, it seems the permanent magnet is not magnetised to its saturation point and the field of the magnet is able to be increased. Permeability values for permanent magnet materials like ferrite are reasonably high. Would the permanent magnet inside the copper coil increase the magnetic field of the solenoid in the same way a soft iron core does?
(I have been unable to find data on the permeability values of permanent magnet materials, possibly because they are not usually used for the purpose I have described!)

Thank you very much for reading this question.
Regards,
Eddie

Answer
Hello Eddie,

I agree with logic of your extrapolation from this statement: "Based on the above quote, it seems the permanent magnet is not magnetised to its saturation point and the field of the magnet is able to be increased." But I would not conclude that therefore the field of the magnet is able to be increased in a way competitive with a soft iron core. I regret that I do not have detailed knowledge about the subject. I wish you success with your efforts.

Regards,
Steve

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Steve Johnson

Expertise

I would be delighted to help with questions up through the first year of college Physics. Particularly Electricity, Electronics and Newtonian Mechanics (motion, acceleration etc.). I decline questions on relativity and Atomic Physics. I also could discuss the Space Shuttle and space flight in general.

Experience

I have a BS in Physics and an MS in Electrical Engineering. I am retired now. My professional career was in Electrical Engineering with considerable time spent working with accelerometers, gyroscopes and flight dynamics (Physics related topics) while working on the Space Shuttle. I gave formal classroom lessons to technical co-workers periodically over a several year period.

Education/Credentials
BS Physics, North Dakota State University
MS Electrical Engineering, North Dakota State University

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