中文摘要：

针对含不同倾角气膜孔的镍基单晶试件的蠕变损伤发展进行了数值模拟,研究了倾角对蠕变特性的影响。气膜孔的倾角分别为0°,15°,30°和45°。结果表明,倾角不同,气膜孔周围的分切应力分布也不同。当倾角为0°,15°和30°时,裂纹扩展方向为θ=±54°,而当倾角为45°时,裂纹沿着θ=±46°的方向进行扩展。倾角为30°的试件有最长的失效寿命。在气膜孔周围的高应力区,分切应力、Mises等效应力和沿拉伸方向的应力σ11均出现了应力松弛现象,且随着时间的延长,应力都达到了稳定值。此外,倾角也影响着蠕变损伤的分布,当倾角为0°,15°,30°和45°时,最大损伤点分别出现在与水平方向成0°,0°,13°和26°的位置。

英文摘要：

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.