Thermal Stability of Nonequilibrium Fe-Ag and Fe-Cu Alloys Produced by Vapor Quenching

X-ray diffraction and Mössbauer effect measurements were carried out for sputtered fcc Fe-Ag and Fe-Cu alloys after being annealed at various temperatures. At temperatures higher than 300°C, the metastable fcc phase decomposes by removing supersaturated Fe atoms. In the fcc Fe-Ag alloys, Fe atoms always give a ferromagnetic hyperfine field component during the clustering process. On the other hand, in the fcc Fe-Cu alloys, the supersaturated Fe atoms form clusters and behave as γ-Fe, giving a small, hyperfine field component.