The Influence of Void Orientation on Stress and Strain Fields for Nickel-based Single Crystal Superalloys Under Creep Loading

Fracture surface of crept nickel-based single crystal superalloy specimen shows that voids play significant role in creep rupture. In this study, the unit cell model containing two voids was established to study the influence of void orientation on the stress and strain distribution for nickel-based single crystal superalloy under creep loading with the creep constitutive relationship based on the crystal slip theory. Three cases were considered with different angle between the line connecting the centers of two voids and loading axis. The distributions of equivalent Mises stress, maximal resolved shear stress and equivalent creep strain have been given for different creep stages. The results show that the void orientation has remarkable influence on the void growth and the stress and strain distribution during creep.