CYCLIC DEFORMATION BEHAVIOUR OF Ni_3(Al,Zr) SINGLE CRYSTAL AT ROOM TEMPERATURE
Ni_3（Al，Zr）单晶循环变形行为的研究

Fully reversed strain-controlled tension-compression tests were performed at room temperature to study cyclic-deformation properties of Ni_3(Al,Zr) single crystal.Both cyclic strain hardening and a tension-compression flow stress asymmetry were recorded,the stress asymmetry becomes more prominent as the strain amplitude becomes larger;the cyclic hardening can divide into initiation and saturation stages.TEM observation showed that there are a profusion superlattic intrinsic stacking faults(SISFs) in fatigued Ni_3(Al,Zr) single crystal samples.The cyclic strain hardening is explained by the dislocation structure.