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The well-densified Ni(3)Al alloys without and with boron addition were fabricated by self-propagation high-temperature synthesis and hot extrusion (SHS/HE) technology. Microstructure investigation showed that Ni(3)Al and Ni(3)Al-1B alloys contained fine grain structure. Analysis of X-ray spectra as well as transmission electron microscopy studies revealed that three phases present in all alloys: gamma-Ni, Ni(3)Al and dispersoids of alpha- Al(2)O(3) and gamma- Al(2)O(3). However, beta-NiAl, Ni(3)B phase and twinned Ni(3)Al crystal are observed in the Ni(3)Al-1B alloy. In addition, dislocations with high density exist in all alloys. The mechanical test showed that the B addition leads to obvious improvement in yield strength and compressive ductility, and compared with the ones synthesized by combustion, SHS/HE synthesized Ni(3)Al and Ni(3)Al-1B alloys exhibit more excellent mechanical properties. (C) 2010 Elsevier Ltd. All rights reserved.