Patent ID: 8197618

Claim:
A method of producing an Ni 3 Al-based intermetallic compound comprising the steps of: performing a first heat-treatment to heat-treat an alloy material comprising greater than 5 at % and not greater than 13 at % of Al, not less than 9.5 at % and less than 17.5 at % of V, 0.5 to 5 at % of Nb, 50 to 1000 weight ppm of B, and the remaining portion being Ni and inevitable impurities at a primary L1 2 phase/A1 phase coexistence temperature at which a primary L1 2 phase and an A1 phase coexist, or at a primary L1 2 phase/A1 phase/D0 a phase coexistence temperature at which a primary L1 2 phase, an A1 phase and a D0 a phase coexist; and performing a second heat-treatment to heat-treat the resulting alloy material at the L1 2 phase/D0 22 phase coexistence temperature, whereby the A1 phase is transformed into an (L1 2 +D0 22 ) eutectoid structure to form a dual multi-phase microstructure, wherein the second heat-treatment is performed at 1173 to 1273K.