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小角度偏离[001]取向的镍基单晶高温合金的蠕变性能受温度、γ'尺寸和应力条件的影响.本文综述了镍基单晶高温合金的[001]取向小角度偏离对蠕变性能的影响.不同程度的偏离引起的不同蠕变性能变化,源于不同的蠕变变形机制.不同的蠕变变形机制对应着引起蠕变发生的不同临界应力.在中温(760～850℃),合金的蠕变性能对[001]取向的角度偏离很敏感,即使角度有轻微变化也会对蠕变性能有明显影响,但是温度高于850℃时,小角度的取向偏离对蠕变性能影响不大.γ'尺寸对小角度偏离的合金蠕变性能的影响受温度制约.在中温,γ'尺寸的变化影响着小角度偏离引起的蠕变性能变化,但是在高温γ'相快速伐化,变形机制和γ'尺寸变化无关.“,”The creep behavior of Ni-based single crystal superalloys with small degree deviation from[001]orientation is strongly influenced by temperature,γ'phase size and the level of applied stress.This research presented a review on effects of small orientation deviation on creep behavior of single crystal superalloys.The variations in the creep properties of alloys with small degree deviation from[001]orientation originate from different deformation mechanisms.Besides,these mechanisms correspond to different threshold stresses which are associated with the occurrence of primary creep and creep rate.At intermediate temperatures (760～850 ℃),the creep behavior of single crystal alloys is highly sensitive to small misorientation but relatively insensitive above 850 ℃.The size of γ'phase is inferred to exert influence on the creep behavior of alloys with orientation deviation at intermediate temperatures.However,at elevated temperatures,the rafting process can be accelerated by higher thermal activation,and thus the mechanical properties become less relevant to the size of γ'precipitates.