ENHANCEMENT OF PIEZOMAGNETIC RESPONSE OF HIGHLY MAGNETOSTRICTIVE RARE-EARTH IRON-ALLOYS AT KHZ FREQUENCIES

The effects of Al and Si additions on the frequency response of highly magnetostrictive Tb-Dy-Fe alloys have been studied. These elements re duced the electrical conductivity of the material, thereby increasing the depth of penetration of ac magnetic fields and extending the opera tional frequency range, Complex permeability measurements were made on doped and undoped polycrystalline samples with the objective of study ing the improvement in energy conversion efficiency at kilohertz frequ encies as a result of the alloying additions, The resulting complex pe rmeability was compared with the values for single crystal specimens o f Tb0.3Dy0.7Fe1.92 at a range of frequencies from 10 Hz to 50 kHz. (C) 1996 American Institute of Physics.