X-Ray Diffraction and Mossbauer Studies of Sigma-Fey Alloys Ball-milled in Vacuum

A coarse-grained tetragonal sigma phase Fe47.4V52.6 at% alloy was ground in vacuum in a vibratory mill. The sigma phase transforms into a bcc alpha phase. A concomitant partial amorphisation of the bcc phase occurs. The near-equiatomic FeV alloys are concluded to behave in the same way as the related FeCr alloys when they are ball-milled in vacuum in similar milling conditions. From Mossbauer spectra, it is concluded that about half of the iron atoms are contained in the amorphous phase in the stationary state. From X-ray diffraction patterns there is also a clear evidence of amorphisation, not seen in previously published studies.