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MM: Fachverband Metall- und Materialphysik
MM 48: Nanostructured Materials IV
MM 48.5: Vortrag
Freitag, 27. März 2009, 11:15–11:30, IFW B
Mechanical Properties of Nanocrystalline Palladium Prepared by Magnetron Sputtering — •Anna Castrup1,2, Torsten Scherer1, Yulia Ivanisenko1, Horst Hahn1,2, In-Suk Choi1, and Oliver Kraft1 — 1Forschungszentrum Kalrsruhe, Germany — 2Technical University of Darmstadt, Germany
Nanocrystalline metals and alloys with grain sizes well below 100 nm often demonstrate unique deformation behaviour and therefore attract a great interest in material science. The understanding of deformation mechanisms operating in nanocrystalline materials is important to predict their mechanical properties.
In the present study Pd films of 1 µm thickness were prepared using UHV rf magnetron sputtering on dog bone shaped Kapton substrates and on Si/SiO2 wafers. The films were sputtered using multilayer technology with an individual layer thickness of 10 nm. This resulted in grain sizes of about 20 nm.
Initial microstructure and texture were characterized using conventional XRD measurements and transmission electron microscopy (TEM) in both cross section- and plane view. The mechanical properties were investigated using tensile testing and nanoindentation at several strain rates. An increased hardness and strength as compared to coarse grained Pd was observed, as well as high strain rate sensitivity. The microstructure in the gauge section after tensile testing was again analyzed using TEM in order to reveal signatures of deformation mechanisms like dislocation motion or twinning.