[en] In intrinsically brittle polycrystalline Ni₃Al alloy, boron ductilizes the intermetallic, meanwhile eliminating the harmful effects of a moisture-containing environment. Macroalloying with manganese makes Ni₃Al inherently ductile. Whether boron addition can further ductilize this alloy and eliminate environmental effects in this case has not yet been determined, although this is very important as regards the elucidation of the mechanism of boron eliminating embrittleness (both intrinsic and extrinsic) of Ni₃Al-based alloys. In this paper, the authors investigate the effect of boron doping on environmental susceptibility of Ni₃(Al, Mn), giving additional evidence that boron doping is capable of eliminating environmental embrittlement in Ni₃Al-based intermetallics