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通过对Ｎｉ_３（Ａｌ，Ｚｒ）单晶在室温下对称拉－压循环变形实验，发现存在拉－压流变应力的不对称性和循环应变硬化现象。应力不对称性随所加循环应变的增大而增大。循环应力响应曲线可分为循环硬化及循环饱和两个阶段。透射电子显微镜（ＴＥＭ）观察表明：疲劳试样中的超结构位错主要以超结构内禀堆垛层错（ＳＩＳＦ）形式存在，这种位错结构是产生应变硬化的主要原因。
Through the symmetrical pull - pressure cyclic deformation test of Ni_3 (Al, Zr) single crystal at room temperature, it is found that there exists the asymmetry of the pull - pressure flow stress and the cyclic strain hardening phenomenon. Stress asymmetry increases with increasing cyclic strain. Cyclic stress response curve can be divided into two stages of cycle hardening and cycle saturation. Transmission electron microscopy (TEM) observations show that the super structural dislocations in the fatigue specimens mainly exist in the form of super structural intrinsic stacking faults (SISF), which are the main causes of strain hardening.