Mechanical properties of fine grained superalloy K4169 with addition of refiners

Grain refinement of superalloy K4169 was achieved by adding refiners into the alloy melt and their effects on the mechanical properties were investigated. The tensile properties at room temperature and 700 ℃ and low cycle fatigue properties at room temperature were compared for both conventional and fine grained test bars. The results indicate that the rupture strength, yield strength, elongation and reduction of area for refined grains are all much superior to those for coarse ones. Whereas the elongation and reduction of area of fine grained samples decrease at 700 ℃. Low cycle fatigue properties of samples with refined grains at room temperature are improved significantly. In addition, the degree of dispersion of low cycle fatigue data of samples with refined grains is diminished.