材料期刊网

Magnetic properties and exchange couplings of nanocomposite (Nd,Y)(2)Fe(14)B/alpha-Fe magnets prepared by mechanical milling have been investigated at low temperatures. With decreasing temperature, due to Y substitution for Nd, an extension of the exchange coupling length in nanocomposite magnets occurs in a wider temperature range. This can be attributed a decreasing anisotropy of the hard-magnetic phase so that more soft-magnetic grains participate the exchange coupling. Close to 135 K, due to the spin reorientation, the hard magnetic phase is not more uniaxail, which leads to a drastic decrease of the magnetic properties of the Nd(2)Fe(14)B-based nanocomposite magnets. (C) 2003 American Institute of Physics.