USE OF A CONDUCTOR SCREEN TO MAGNETIZE NDFEB MAGNETS

The magnetizer presented in this paper consists of a magnetic core mad e with silicon iron sheets with a large airgap in which the permanent magnets to be magnetized are located.This magnetic structure is energi zed by two symmetrical coils placed on the central leg above and below the airgap. The cross section of the airgap is four times the area of the permanent magnet, so with a copper plate that surrounds the magne t (not completely), effective concentration of the nux density lines i s obtained. The copper plate was called ''Electromagnetic Conductor Sc reen''. The Capacitor-Discharge-Bank was rated 1080 mu F, 2000V and 3. 5 Tesla were obtained in the central airgap. The paper presents the ex perimental results and theoretical analysis used to evaluate the condu ctor screen time-constant of the proposed magnetizing system.