Temperature Dependence of Magnetization of Amorphous TM70Cr5Si10B15 (TM = Fe, CO, Ni) Alloys

We report the salient features of the magnetic properties of amorphous TM_(70)Cr_5Si_(10)B_(15) (TM=Fe, CO, Ni) alloys. The temperature dependence of magnetization for amorphous ribbons were measured by a SQUID and a VSM from 5 K to 700 K under an external field of 10 kOe. Except TM_(70)Cr_5Si_(10)B_(15) that shows a paramagnetic behaviour, both Fe and Co based amorphous alloys show a typical ferromagnetic thermo-magnetization curves. For these two ferromagnetic alloys, the saturation magnetization in the temperature range from 5 K to about 0.4 Tc can be descrived by the Bloch relation, Ms (T) = Ms(0) [1-BT^(3/2)-CT^(5/2)]. The spin wave stiffness constants and the range of exchange interaction were analyzed from the magnetization behaviour. The variation of the magnetic properties are discussed and compared with the composition of the alloys.