【摘要】 针对切口圆棒试样,利用有限元方法模拟了国产镍基单晶合金DD3[001]取向的蠕变性能。计算结果表明:切口半径对应力分布有显著的影响,切口半径越大,蠕变应力越大;切口深度对蠕变性能的影响不大;切口半径对持久寿命的影响作用非常大,切口半径越小,持久寿命越大。在所研究范围内,切口对试样持久寿命的强化作用,得到他人试验的验证。更多还原

【Abstract】 Seven U-type and V-type circular notched specimens of nickel-base single crystal DD3 had been creep numerical simulated under tensile orientation and 950℃ with the software MARC. These finite element models are capable of representing complex stress state. The durability lifetimes including circular notch and smooth specimens were investigated based on the maximum shear stress amplitude. The results show that the notch size has strong influence on stress distributions and lifetime. The resolved shear stresses increase with the increasing of notch radii. For the same net-section stress, the notched specimens have a longer lifetime than the smooth specimen. This result confirms to P. Lukas’ research.更多还原