Synergistic influence of cerium and yttrium micro-addition on microstructure and mechanical tensile properties of K465 nickel based superalloy

•Ce element is found to distribute in the internal grains of K465.•Y element is shown to combine towards with the MC carbides.•The MC carbides are biased toward precipitation at grain boundaries.•8.35 % increasement in ultimate tensile strength for Ce + Y addition. The microstructures and room temperature tensile properties of a nickel-based cast superalloy K465 were investigated with the cerium (Ce) and cerium + yttrium (Y) additions, respectively. In K465 superalloys, Ce element was found to distribute in the internal grains of K465. And, the Y element was shown to combine towards with the MC carbides. The tensile properties experienced increasement with the addition of Ce and Y, 0.86 % increasement for Ce addition and 8.35 % increasement for Ce + Y addition. The synergistic effect of rare earths element plays a positive role in the mechanical properties of the nickel based superalloy.