A TEM AND CEMS STUDY OF BCC FE-NI-CR THIN-FILMS

Mossbauer spectroscopy, X-ray diffraction and transmission electron mi croscopy are used to study ferromagnetic Fe-Ni-Cr films prepared by io n-beam sputtering. The X-ray diffractograms of deposits reveal the cry stalline character of these materials, while transmission electron mic roscopy determines the nucleation and morphological growth stages. A p hase transition takes place at temperatures higher than 750 K. Evidenc e is found that, during the transition, the ferromagnetic part of the Mossbauer spectra splits up into two components, thus indicating the e xistence of two iron sites. The index n and activation energy Q in the Johnson-Mehl-Avrami plot are found to be 0.68 and 366 kJ mol-1, respe ctively.