The electron channelling contrast technique applied to the characterisation of dislocation structures in the vicinity of a fatigue crack
The electron channelling contrast technique applied to the characterisation of dislocation structures in the vicinity of a fatigue crack
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电子沟道对比技术应用于疲劳裂纹附近位错结构的表征
DOI：
10.1111/j.1460-2695.1997.tb01510.x
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发表时间：
1997
影响因子：
3.7
通讯作者：
R. Stickler
中科院分区：
文献类型：
--
作者：
D. Chen;D. Melisova;B. Weiss;R. Stickler
- 在这项调查中，电子衍射对比（ECC）技术在扫描电子显微镜（SEM）被施加到显示在表面疲劳裂纹附近的位错结构相比，那些循环变形的再结晶多晶铜。疲劳裂纹周围的塑性区被认为是由一个最里面的区域包含细胞，其次是一个区域包含密集的静脉和PSB，周围的结构松散的静脉，束和循环补丁典型的循环变形的矩阵。给出了疲劳裂纹附近位错结构与循环应力-应变研究中得到的塑性应变幅值之间的关系。确定了典型的损伤累积区域，并建立了表面疲劳裂纹的塑性应变等值线。基本上是非破坏性的ECC技术是特别适合于确定从表面层的样品内部在大试样面积的介观位错结构的变化。
— In this investigation the Electron Channelling Contrast (ECC) technique in scanning electron microscopy (SEM) was applied to reveal the dislocation structures in the vicinity of surface fatigue cracks in comparison to those of cyclically-deformed recrystallized polycrystalline copper. The plastic zone around a fatigue crack was found to consist of an innermost region containing cells, followed by a region containing dense veins and PSBs, surrounded by a structure of loose veins, bundles and loop patches typical of the cyclically deformed matrix. A relation between plastic strain amplitude values deduced from cyclic stress-strain investigations and the dislocation structures near fatigue cracks are given. Typical regions of damage accumulation were identified and plastic strain contours for surface fatigue cracks established. The essentially non-destructive ECC technique is particularly suited to identify the changes in mesoscopic dislocation structures from surface layers to the interior of specimens over large specimen areas.