Crack initiation anisotropy of Ni-based SX superalloys in the very high cycle fatigue regime

The anisotropic fatigue properties of three Ni-based SX superalloys (AM1, CMSX-4 and MC-NG) were investigated in the very high cycle regime at 20 kHz, R = ?1 750 °C. testing shows that [111] orientation has higher lives stresses lower low compared to standard [001] orientation. At stresses, resolved shear stress on octahedral slip systems explains anisotropy effect. pseudo-cube matrix becomes prominent deformation mechanism over ??-shearing orientation, resulting comparatively properties.