锆-4的反复弯曲高周疲劳性能及其显微组织

测定了再结晶状态锆－４合金反复弯曲高周疲劳寿命曲线，得出其疲劳极限约为２５０ＭＰａ。疲劳试样用ＳＥＭ观察表明：锆－４表面为波纹状滑移特征。驻留滑移带、晶界是锆－４主要的疲劳裂纹萌生区域。疲劳变形亚结构的ＴＥＭ分析表明：｛１０１０｝柱面滑移与孪生是其主要的变形方式；锆－４典型的位错组态是两组或多组平行位错线。与纯锆相比，锆－４更易产生交滑移。

REVERSAL BENDING FATIGUE PROPORTIES AND MICROSTRUCTURE OF ZIRCALOY 4

Reversal bending fatigue lifetime curves of recrystallized Zircaloy 4 were measured.The fatigue limit of Zircaloy 4 at room temperature is about 250 MPa.SEM analysis shows that Zircaloy 4 exhibits the character of wavy slipping.PSBs and grain boundary cracking are the primary fatigue cracking sources.TEM examination displays that {10 1 0} prismatic slipping and twinning are the primary plastic deformation modes,and the typical dislocation structure is the two sets of parallel dislocation lines.Comparing with a commercial purity zirconium,cross slip is easier in Zircaloy 4.