THERMAL-STABILITY OF HIGH-CONCENTRATION FE-CU ALLOYS PRODUCED BY VAPOR QUENCHING

X-ray diffraction and Mossbauer effect measurements were carried out for sputtered Fe//1// minus // multiplied by Cu// multiplied by alloys as a function of annealing temperature. Metastable b. c. c. and f. c. c. phases undergo a structural relaxation around 470K. At temperatures higher than 570K, the metastable phases decompose by removing supersaturated Cu and Fe atoms. During the phase separation process, the ejected Cu and Fe atoms form clusters which initially have a b. c. c. or f. c. c. structure and transform to particles as their sizes grow beyond a critical value.