Microstructural evolution of Ni3Al-based alloys, during various stages of plastic deformation was investigated by conventional transmission electron microscopy. Significant grain refinement was observed. The finest grains (100nm) were even a hundred times smaller than the initial ones (10μm). Various aspects of strengthening mechanisms were indicated: deformation and solid solution strengthening, hardening due to antiphase boundary formation and martensitic transformation of the NiAl interdendritic phase.

TEM Investigations of Ni3Al-Based Intermetallic Polycrystals. Jozwik, P., Jezierska, E., Bojar, Z.: Materials Chemistry and Physics, 2003, 81[2-3], 448-51