57Fe Mössbauer studies of amorphous Pd40(NiFe)40P20 alloys

Abstract

Zero-field 57Fe Mossbauer spectroscopy has been used to study the magnetic properties of an amorphous melt-spun Pd40Ni40−x FexP20 (x=5, 10, 17.5, 20) series. The alloys show quadrupole split doublets at room temperature indicating paramagnetic behaviour. At low temperatures the Mossbauer spectra are sextets due to the onset of long range order. The transition temperatures increase with Fe concentration from 12±2 K for Pd40Ni35Fe5P20 to 42.0±2.0 K for Pd40Ni20Fe20P20. The hyperfine field was found to follow Hf(0)(1−T/Tc)β over the critical region with the β exponent being close to 0.4.