Electron channelling contrast technique applied to the characterization of dislocation structures in the vicinity of a fatigue crack

被引：0

作者：

Chen, D.L. ^{[1
]}

Melisova, D. ^{[1
]}

Weiss, B. ^{[1
]}

Stickler, R. ^{[1
]}

机构：

[1] Univ of Vienna, Vienna, Austria

来源：

Fatigue and Fracture of Engineering Materials and Structures | 1997年 / 20卷 / 11期

关键词：

Copper - Crack propagation - Deformation - Fatigue of materials - Nondestructive examination - Plasticity - Polycrystalline materials - Scanning electron microscopy - Strain - Stress analysis;

D O I：

暂无

中图分类号：

学科分类号：

摘要：

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.

引用

页码：1551 / 1561