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Name: Stephen
Status: other
Age: 30s
Location: N/A
Country: N/A
Date: 2000-2001


Question:
Is there such a material that can prevent two permanent magnets from attracting each other within a distance of 10mm?


Replies:
The simplest way would be to arrange them north pole to north pole, then they would repel each other rather than attract each other.

A more elaborate solution which will greatly reduce (but not eliminate) the attraction would be to place a magnetic shielding structure between them. These are typically made of multiple layers (spaced with a non-magnetic material such as aluminum) of a material with a very high affinity for magnetic fields, such as mu-metal. The magnetic fields are 'trapped' in the layers of the mu-metal and do not extend much beyond it.

The catch 22 is that the magnets are strongly attracted to the shield so they both still have a strong force pulling them toward the shield, even though they are not interacting with the other magnet.

Dr. Bradburn



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