Movement of Dislocations in the Sub-Surface of a Polycrystalline Metal by Cavitation Peening Observed by Transmission Electron Microscopy

Osamu Takakuwa¹, Akihiko Chiba², Hitoshi Soyama¹

¹Department of Nanomechanics, Graduate School of Engineering, Tohoku University, Sendai, Japan.
²Institute for Materials Research, Tohoku University, Sendai, Japan.

DOI: 10.4236/msa.2015.62017                

Abstract

The impact produced when cavitation bubbles collapse can be utilized to modify surfaces in the same way as shot peening and it is called cavitation peening (CP). CP is one of a number of surface modification techniques used to improve the fatigue strength of metallic materials by introducing compressive residual stress. Although it has been shown by an X-ray diffraction method that CP decreases the micro-strain related to dislocations in the sub-surface of a polycrystalline material, the mechanism for this decrease is unclear. In this paper, the movement of dislocations by CP was observed using transmission electron microscopy (TEM).

Keywords

Microstructure, Transmission Electron Microscopy, Dislocation, Surface Modification, Cavitation

Conflicts of Interest

The authors declare no conflicts of interest.

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