Thermal stability and hyperfine interactions of mechanically alloyed Fe–Ge phases
Artykuł w czasopiśmie
| Status: | |
| Autorzy: | Jartych Elżbieta, Oleszak Dariusz, Kubalova L. M. , Vasilyeva O. Ya, Żurawicz Jan , Pikula Tomasz, Fedotov S.A. |
| Rok wydania: | 2007 |
| Wersja dokumentu: | Drukowana | Elektroniczna |
| Język: | angielski |
| Numer czasopisma: | 1-2 |
| Wolumen/Tom: | 430 |
| Strony: | 116 - 122 |
| Impact Factor: | 1,455 |
| Web of Science® Times Cited: | 8 |
| Scopus® Cytowania: | 5 |
| Bazy: | Web of Science | Scopus |
| Efekt badań statutowych | NIE |
| Materiał konferencyjny: | NIE |
| Publikacja OA: | NIE |
| Abstrakty: | angielski |
| Mechanical alloying method was applied to prepare the Fe75Ge25, Fe62Ge38 and Fe33.3Ge66.7 alloys. X-ray diffraction, differential scanning calorimetry and Mössbauer spectroscopy were used as complementary methods to obtain structural data and hyperfine interaction parameters for the as-milled as well as the heated samples. After mechanical alloying process the disordered α-Fe(Ge) solid solution was formed in the case of Fe75Ge25 composition and it was characterized by the broad hyperfine magnetic field distribution with the average field of about 25 T. Heat treatment up to 873 K resulted in the formation of the mixture of three ordered phases and α-Fe(Ge) solid solution. The ordered phases were: metastable D03 phase with two hyperfine magnetic fields of 32.8 and 20.2 T and two equilibrium phases—hexagonal ɛ and cubic ɛ′ with fields of about 24.6 and 23.6 T, respectively. After heating up to 973 K this mixture transformed into the mixture of ɛ and ɛ′ phases. In the case of Fe62Ge38 composition the hexagonal β-Fe3Ge2 phase was obtained during mechanical alloying process. This phase was stable after heat treatment up to 973 K. The as-milled and heated samples were characterized by similar Mössbauer spectra, which were a superposition of the sextets with various hyperfine magnetic fields what reflected different configurations of germanium atoms around 57Fe atoms. In the case of Fe33.3Ge66.7 composition the ordered tetragonal FeGe2 phase was obtained and it was stable during heat treatment up to 973 K. Mössbauer measurements revealed the single paramagnetic line with the isomer shift of 0.30(1) mm/s characteristic for the FeGe2 intermetallic phase. |
