by Wang, Xi-Shu; Yan, Cheng-Kun; Li, Ying; Xue, Yibin; Meng, Xiang-Kang; Wu, Bi-Sheng

Three-point bending tests on nanocrystalline Cu or Cu/Ni-film/Cu-substrate samples were conducted in-situ with scanning electron microscopy (SEM) observations. The SEM in-situ observations show undulation deformation of the surface of thin film, as the thin film fractures easily at the concave–convex points of deformation and multi-cracks appear on the surface of the thin film in a periodic fashion. The critical wavelength of undulation is calculated based on experimental observations, which are comparable with the theoretical predictions. For the Cu/Ni multi-layered films/substrate structures, the micro-cracking pattern depends on the interfacial strength between the film and the substrate, rather than the interfacial strength between the layers of films.

DOI: 10.1007/s10704-008-9257-8
Online Date: 9/15/2008
Print publication date: 6/1/2008
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