Autor: |
Chia-Hung Lee, Erh-Ju Lin, Jyun-Yang Wang, Yi-Xuan Lin, Chen-Yu Wu, Chung-Yu Chiu, Ching-Yu Yeh, Bo-Rong Huang, Kuan-Lin Fu, Cheng-Yi Liu |
Jazyk: |
angličtina |
Rok vydání: |
2021 |
Předmět: |
|
Zdroj: |
Nanomaterials, Vol 11, Iss 7, p 1630 (2021) |
Druh dokumentu: |
article |
ISSN: |
2079-4991 |
DOI: |
10.3390/nano11071630 |
Popis: |
Tensile tests were carried on the electroplated Cu films with various densities of twin grain boundary. With TEM images and a selected area diffraction pattern, nano-twinned structure can be observed and defined in the electroplated Cu films. The density of the nano-twin grain structure can be manipulated with the concentration of gelatin in the Cu-sulfate electrolyte solution. We found that the strength of the Cu films is highly related to the twin-boundary density. The Cu film with a greater twin-boundary density has a larger fracture strength than the Cu film with a lesser twin-boundary density. After tensile tests, necking phenomenon (about 20 μm) occurred in the fractured Cu films. Moreover, by focused ion beam (FIB) cross-sectional analysis, the de-twinning can be observed in the region where necking begins. Thus, we believe that the de-twinning of the nano-twinned structure initiates the plastic deformation of the nano-twinned Cu films. Furthermore, with the analysis of the TEM images on the nano-twinned structure in the necking region of the fractured Cu films, the de-twinning mechanism attributes to two processes: (1) the ledge formation by the engagement of the dislocations with the twin boundaries and (2) the collapse of the ledges with the opposite twin-boundaries. In conclusion, the plastic deformation of nano-twinned Cu films is governed by the de-twinning of the nano-twinned structure. Moreover, the fracture strength of the nano-twinned Cu films is proportional to the twin-boundaries density. |
Databáze: |
Directory of Open Access Journals |
Externí odkaz: |
|