New Systems of Rare Earth Permanent Magnets for Generation of Extrahigh Magnetic Fields

Various systems, which are composed of rare-earth permanent magnets and generate strong magnetic fields, are calculated. Strong fields are taken to mean the fields with the strength, which exceeds the magnet induction. Calculated values of the strength of strong fields can mount to 20–150 kOe. Depending on form of domains where this fields are localized they can be classified as linear and point fields, the corresponding systems can be named linear and point as well. It was shown that the maximal linear field can be obtained in Halbach cylinder (prism), in which this field tends to Hx = 4πMs ln(a/x) with increasing of number of component sectors. The maximal point field is reached in systems composed of many conical magnets, divided by many sectors. The strength of such field tends to the value Hx = 8πMs ln(a/x). Experimental values of strong fields measured in some systems by various methods are in good agreement with calculated data.