Ribbons of Fe100−xGax (x=15, 17.5, 19.5 and 22.5) were prepared by rapid solidification from the melt. 57Fe Mössbauer spectroscopy and high resolution neutron diffraction have revealed that Fe1−xGax alloys with x=15 and 17.5 have the disordered bcc (A2) structure even after annealing, but the alloy with x=19.5 developed the short-range ordered D03 phase when annealed. The x=22.5 alloys showed mainly D03 phase with a fraction of bcc phase. A fraction of the bcc phase transformed into D03 phase and the long-range ordering of D03 phase was improved after annealing. 57Fe Mössbauer spectra showed no observable L12 phase in any samples even though less than 1% volume of L12 phases has been found in the annealed samples by neutron diffraction. The additional absorption at hyperfine field of 25 T in x=22.5 samples was regarded as a result of imperfect D03 structure, rather than L12 phase.
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机译：通过从熔体中快速凝固来制备Fe100-xGax（x = 15、17.5、19.5和22.5）的带。 57FeMössbauer光谱和高分辨率中子衍射表明，即使退火后，x = 15和17.5的Fe1-xGax合金也具有无序的bcc（A2）结构，但是x = 19.5的合金在退火时会形成短程有序D03相。 x = 22.5合金主要显示为D03相，一部分为bcc相。退火后，一部分bcc相转变为D03相，并且D03相的长程有序化得到改善。 57FeMössbauer光谱显示，即使通过中子衍射在退火的样品中发现L12相的体积少于1％，任何样品中都没有可观察到的L12相。 x = 22.5样品中25 T处超精细场的额外吸收被认为是D03结构不完善而不是L12相的结果。
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