Although amorphous phases produced by mechanical alloying (MA) in the Ni-Mo system have been reported before. It has not been presented the influence of using different milling devices and atmospheres. This work is focused to the characterization of amorphous structures thus obtained in a Mo-47 at. % Ni alloy. Selected composition corresponds to the equiatomic NiMo intermetallic. The characterization was carried-out by XRD, SEM-EDS, DSC and TEM. High resolution XRD reveals that the MA′ed products undergo partial amorphization, as shows Figure 1. The main difference in the patterns is a region that corresponds to typical Nickel reflections. Nickel preferential amorphization after milling was evident. Apparently, a major grade of amorphization was attained when using the Simoloyer mill. A rough crystallite size was calculated using Scherrer equation, which reveals that this parameter reached its minimum value with the Simoloyer mill. During DTA analysis, it was observed the presence of an exothermic peak in all samples.