Numerical Simulation on the Creep Damage Evolution of Nickel-Based Single Crystal Specimens with Slant-Angled Film Cooling Holes

Numerical calculations have been performed to study the creep damage evolution of nickel-based single crystal specimens with slant-angled film cooling holes. The emphasis is the effect of different slant angles on creep properties. The slant angles are 0°, 15°, 30° and 45°. The results show that the distributions of the resolved shear stress around film holes are different under different slant angles. The directions of crack propagation are θ=±54° when α=0°, 15°, 30°; however when α=45° the crack propagation directions are along θ=±46°. The specimen with α=30° has the longest failure life. In the higher stress region near the cooling hole, the phenomenon of stress relaxation will appear, such as resolved shear stress, Mises equivalent stress and stress σ11. And with the time increasing, they reach stable values. Different specimens have different damage distributions. The maximum damage points appear at locations 0°, 0°, 13° and 26° from horizontal direction when the slant angles are 0°, 15°, 30° and 45°, respectively. And thickness has influence on the distribution of resolved shear stress along the holes.