The influence of carbon on the hyperfine interaction and Curie temperatures of amorphous Fe84B16−xCx*

Abstract

Amorphous Fe84B16−xCx (0?x?10) have been studied by 57Fe Mössbauer spectroscopy. The Curie temperature (TC) increases monotonically with carbon concentration. Well-defined hyperfine field distributions {P(H) } at 4.2 K have been found. The distribution width as well as the asymmetry of P(H) increase smoothly as carbon replaces boron. The mean hyperfine field and the average iron moment are found to be proportional. There is a small change in the temperature dependence of the reduced hyperfine field as the carbon concentration increases. This suggests the distribution width of the exchange interactions varies slightly with carbon concentration.