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Permanent magnets have groupings of "bodies" of alloyed materials that under pressure and elevated temperature are subjected to an intense short-duration magnetic field. Those bodies align based upon their internal magnetic potential. That potential is determined by the alignment of micro crystaline forms of electro-energetic elements such as Iron. Such elements have dipoles associated with their microcrystaline form. That dipole is created by the "cell" structure of the crytal being electro deficient in one plane. This plane is the longitudinal axis of that crystal's magnetic dipole. Now think of a sliver of Iron like the needle of a compass. When the temperature and pressure are increased in its surroundings the sliver is freed up to rotate and associate with any magnetic dipole that can influence it. The surroundings that it is in is other slivers that are trying to line up as well. when a magnetic field of sufficient strength is applied to this matrix in this condition then all of the slivers line up together (this is instantaneous and so the applied magnetic field need last only a thousandth of a second). At this point the magnet is cooled. Yes, if you wait too long to cool the magnet it will loose quite a bit of magnetism, but the rate of loss is minimised by several factors. One is that the matrix can be a ceramic mixture rather than an alloy allowing for lower temperatures in manufacture, but this also has the tendency to be demagnetised by stronger fields. Permanent magnets are permanent only as long as they are not subjected to a magnetic field of sufficient strength to negate or erase the field in the magnet, also based upon material resistance to loss of magnetism (see the ceramic above). They are also subject to extreme temperatures (as seen in the manufacturing process). I hope this answers you r questions to some degree, see ya, BAT
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