Novel Amorphous Fe-Zr-Si(Cu) Boron-free Alloys

Novel amorphous Fe(80)(Zr(x)Si(20-x-y))Cu(y) boron-free alloys, in which boron was completely replaced by silicon as a glass forming element, have been prepared in the form of ribbons by a melt quenching technique. The X-ray diffraction and Mossbauer spectroscopy measurements revealed that the as-quenched ribbons with the composition of x=6-10 at % and y=0, 1 at.% are predominantly amorphous. DSC measurements allowed the estimation of the crystallization temperatures of the amorphous alloys. The soft magnetic properties have been studied by the specialized rf-Mossbauer technique in which the spectra were recorded during an exposure of the samples to the rf field of 0 to 20 Oe at 61.8 MHz. Since the rf-collapse effect observed is very sensitive to the local anisotropy fields it was possible to evaluate the soft magnetic properties of amorphous alloys studied. The rf-Mossbauer studies were accompanied by the conventional measurements of the quasi-static hysteresis loops from which the magnetization and coercive fields were estimated. It was found that amorphous Fe-Zr-Si(Cu) alloys are magnetically very soft, comparable with those of the conventional amorphous B-containing Fe-based alloys.