Bulk Fe2B crystal fabricated by mechanical ball milling and plasma activated sintering

•New phase do not appear as milling of Fe and B powders reaches 10 h and above.•The phases in samples contain Fe3B and α-Fe at sintering of 1173K.•The single bulk Fe2Bcan be fabricated at sintering temperature reaching 1273K.•Compared with grain size at 1173K, Fe2B at 1273K and 1373K becomes much bigger. Bulk Fe2B crystals were fabricated with Fe and B mixed powders by mechanical ball milling and plasma activated sintering (PAS). The results indicate that, as milling time reaches 10h and above, the diffraction peaks of B powders will vanish and new phases will not appear. With increasing milling time from 1h to 40h, the distribution of mixed powders gradually becomes uniform and compact; however, at milling time from 40h to 50h, the uniformity and relative density have no distinct change. At sintering temperature of 1173K, the phase compositions of sintered samples are composed of Fe3B and α-Fe. At 1273K and 1373K, bulk Fe2B can be fabricated and the relative density of these two samples has no distinct difference, except the difference of Fe2B sizes. In additional, compared with grain size at 1173K. the grain sizes at 1273K and 1373K sharply become much bigger. Furthermore, due to the Fe2B size at 1373K larger than that at 1273K, Fracture toughness of Fe2B at 1273K distinctly decreases from 3.96MPam1/2 to 3.01MPam1/2.