| Nanocrystalline (nc) copper was produced by severe plastic deformation through the equal-channel angular pressing (ECAP) method. Surface morphology of pure copper was studied by means of an atomic force microscope (AFM) and scanning electron microscope (SEM) techniques on different scales and stages under tensile loading. The main objectives of this study are (i) examination of mechanisms of damage evolution and fracture and (ii) exploitation of the capabilities of AFM to accurately perform an analysis of the surface features of nc copper to provide the basis necessary for the development of a model for explaining the specific mechanical properties of nano-materials. It is shown that the AFM can be extremely useful for the investigations of a surface topography. It is confirmed that the dislocation-dominated plasticity and nano-voids formation are the dominant deformation mode although the deformation evolution and fracture occur through the interplay of various microstructural features. |
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