MAGNETIC MOMENT,CURIE TEMPERATURE AND SPIN WAVE EXCITATION FOR AMORPHOUS Fe_(90-x)Si_xZr_(10) ALLOYS

The magnetization curves at 1.5 K and thermomagnetic curves for amorphousFe_(90-x)Si_xZr_(10)(x=0,4,7 and 10)alloys prepared by the drum spinning technique have beenmeasured with an extracting sample magnetometer.It is obtained that the average magneticmoment,,per magnetic atom and Curie temperature,T_c,in the amorphous FeSiZr alloysincrease with increasing Si content.The and T_c are found to be quite small,compared withamorphous FeSiB alloys.This unusual behavior is suggested to be due to the presence of theFe—Fe antiferromagnetic interactions.The temperature dependence of magnetization at lowertemperature is in accordance with Bloch's T~(3/2) law.Calculation shows that the spin wavestiffness constant,D,increases with increasing Si content from 0.37 meV·nm~2 for x=0 to0.538 meV·nm~2 for x=10.The values ofindicate that the range of the exchangeinteraction is roughly the mean atomic distance of nearest neighbours.