Increased tensile strength and elongation of the Ni–Fe based polycrystalline cast superalloy via the trace addition of TiC nanoparticles

In this work, a Ni–Fe based cast superalloy (K214) containing 0.02 wt% TiC nanoparticles was fabricated by the vacuum induction melting, and the effects of TiC nanoparticles on the microstructure and tensile properties of the alloys were investigated. The trace addition of TiC nanoparticles effectively refined the as-cast grains, promoted the coarsening of secondary dendrite arms, and reduced microsegregation. The yield strength, ultimate tensile strength and elongation at room/elevated temperatures were simultaneously improved, which could be ascribed to reduced microsegregation and refined γ′ precipitates. This work provides a strategy for the effective improvement in the mechanical properties of cast superalloys fabricated by the conventional casting process.