The Effect of TiC–TiB2 Dual-Phase Nanoparticles on the Microstructure and Mechanical Properties of Cast Ni–Fe-Based Superalloys

TiC–TiB2 dual-phase nanoparticles were added into a Ni–Fe-based cast superalloy and their effects on the microstructure and mechanical properties were compared to those of a Ni–Fe-based superalloy with the addition of TiC nanoparticles. The addition of TiC nanoparticles led to the precipitation of a higher volume fraction of carbides. Compared to the addition of TiC, the addition of TiC–TiB2 nanoparticles not only led to the precipitation of carbides but also promoted the formation of flaky borides and a reduction in the precipitation of the Laves phase. The strengthening effect of TiC–TiB2 nanoparticles on the mechanical properties of Ni–Fe-based superalloys was stronger than that of TiC nanoparticles due to more secondary γ’ precipitates. This study provides valuable insights for selecting ceramic nanoparticles to increase the mechanical properties of cast Ni–Fe-based superalloys.