Deformation-induced grain growth and twinning in nanocrystalline palladium thin films

Beilstein Journal of Nanotechnology

Ankush Kashiwar¹  Jochen Lohmiller²  Patric A. Gruber²  Christian Kübel³  Michael Kerber³  Aaron Kobler⁴  Anna Castrup⁴  Horst Hahn⁴  Jonathan Schäfer⁵  Karsten Albe⁵ 

[1] Department of Metallurgical and Materials Engineering, Visvesvaraya National Institute of Technology (VNIT), Nagpur 440 010, Maharashtra, India;Karlsruhe Institute of Technology (KIT), Institute for Applied Materials (IAM), P.O. Box 3640, 76021 Karlsruhe, Germany;Karlsruhe Institute of Technology (KIT), Institute of Nanotechnology (INT), 76021 Karlsruhe, Germany;Technische Universität Darmstadt (TUD), KIT-TUD Joint Research Laboratory Nanomaterials, 64287 Darmstadt, Germany;Technische Universität Darmstadt (TUD), Petersenstr. 32, 64287 Darmstadt, Germany;

关键词: ACOM-TEM;    deformation mechanism;    nanostructured metals;    tensile testing;    XRD;   

DOI  :  10.3762/bjnano.4.64

来源: DOAJ

【 摘 要 】

The microstructure and mechanical properties of nanocrystalline Pd films prepared by magnetron sputtering have been investigated as a function of strain. The films were deposited onto polyimide substrates and tested in tensile mode. In order to follow the deformation processes in the material, several samples were strained to defined straining states, up to a maximum engineering strain of 10%, and prepared for post-mortem analysis. The nanocrystalline structure was investigated by quantitative automated crystal orientation mapping (ACOM) in a transmission electron microscope (TEM), identifying grain growth and twinning/detwinning resulting from dislocation activity as two of the mechanisms contributing to the macroscopic deformation. Depending on the initial twin density, the samples behaved differently. For low initial twin densities, an increasing twin density was found during straining. On the other hand, starting from a higher twin density, the twins were depleted with increasing strain. The findings from ACOM-TEM were confirmed by results from molecular dynamics (MD) simulations and from conventional and in-situ synchrotron X-ray diffraction (CXRD, SXRD) experiments.

【 授权许可】

Unknown