Mössbauer spectroscopic studies of Fe-20 wt.% Cr ball milled alloy

Abstract

Interesting differences were noticed in the alloying process during ball milling of Fe-10 wt.% Cr and Fe-20 wt.% Cr alloys by 57 Fe Mössbauer spectroscopic studies. In both cases, there is almost no diffusion of Fe in Cr or vice versa up to 20 h of milling time. As the powders are milled for another 20 h substantive changes occur in the Mössbauer spectra showing atomic level mixing. But the two compositions behave differently with respect to alloying. Fe-20 wt.% Cr sample does not differ much in the hyperfine field distribution as it is milled from 40 to 100 h. On the other hand, the hyperfine field distribution keeps on changing with milling time for Fe-10 wt.% Cr sample even up to 100 h of milling. The average crystallite size is found to be 7.5 nm for Fe-10 wt.% Cr and 6.5 nm in Fe-20 wt.% Cr after milling.

Mixing characterization of mechanically milled Fe75Si15M10 powders using Mössbauer spectroscopy

“…The observation of paramagnetic component and diffusion of iron into minority element is in contrast with our earlier work on the Fe-Cr ball milled samples [15,16], where we have observed predominantly magnetic components with very small contribution (less than 5%) of paramagnetic component. It was concluded that diffusion of Cr atoms into the Fe matrix was preferred over the diffusion of Fe in Cr.…”

“…In the present paper we describe studies on these alloys using Mössbauer spectroscopy. It was found for the Fe-Cr systems with the help of Mössbauer spectroscopy that during the course of milling Cr preferentially diffuses in the Fe matrix but iron does not diffuse in the Cr lattice [15,16]. As a result, sextets of decreasing hyperfine field (B hf ) value evolved with milling time but no significant paramagnetic component was created.…”

Distribution of Cr atoms in the surface zone of Fe-rich Fe–Cr alloys quenched into various media: Mössbauer spectroscopic study

“…There is a great body of papers relevant to the matter in which the Mössbauer spectroscopy was used as a research tool e.g. [148][149][150][151][152][153][154][155][156][157][158][159][160][161][162]. MS being sensitive to local arrangements of atoms permits following the alloying process versus milling time.…”

Структурно-фазовые превращения и эволюция ближнего порядка в системе Fe-Cr в процессе механического сплавления

“…Одним из способов улучшения физико-механических свойств материала является его получение в наноструктурированном состоянии (размер зерен менее 100 nm). Существует много работ, касающихся получения нанокристаллических сплавов Fe−Cr с использованием механического сплавления (МС) [2][3][4][5][6][7][8][9]. Здесь важным вопросом является изучение механизмов деформационного атомного перемешивания.…”

“…Здесь важным вопросом является изучение механизмов деформационного атомного перемешивания. Так, в [9] для порошковых смесей Fe−Cr, содержащих до 20 at.% Cr, показано, что процесс МС происходит за счет диффузии Cr в Fe. МС более богатых хромом смесей (до 48 at.% Cr) изучалось в работах [10][11][12][13], в которых было показано изменение механизма МС при концентрации хрома в исходной смеси более 30 at.%.…”