Modification of surface hardness for dual two-phase Ni3Al–Ni3V intermetallic compound by using energetic ion beam and subsequent thermal treatment

Dual two-phase Ni3Al–Ni3V intermetallic compound with the ordered structure was irradiated with 16 MeV Au5+ ions at room temperature. The observation by a transmission electron microscope has revealed that the lattice structure of this intermetallic compound changes from the ordered structure to the disordered A1 (fcc) structure by the ion irradiation, which accompanies a remarkable decrease in the surface hardness. The annealing treatment at elevated temperatures for the irradiated specimen induces the recovery of surface hardness. The present experimental result shows that the combination of energetic ion irradiation and the thermal treatment could be a means of modification for the workability of dual two-phase Ni3Al–Ni3V intermetallic compound.