Metallic Nanoimprinting – Nanoscale surface structuring by confined plastic deformationThursday (27.09.2018) 12:00 - 12:15 S1/01 - A03 Part of:
In this presentation, a new metallic nanoimprinting process is presented, which allows the surface structuring on the micro and nanometer size range. Nanoscale surface structures of metals promises new functional properties like an enhanced heat transfer, reduced friction or super hydrophobic surfaces. Surface structuring relies often on a direct structuring of the materials by methods like femtosecond laser processing, electrolytic processing or lithographic methods. Nanoimprinting however uses a structured die, which is pressed onto the surface and local plastic deformation yields the surface structure. The flow behavior of metals on the nanoscale, however is not fully understood. In this work, a scale bridging experimental approach is used to explore the flow behavior of metals and alloys with different microstructure and work hardening behavior. Used as forming tools are flat punch diamond indenter, with diameters ranging from 100 µm – 5 µm and structure sizes between 15 µm down to 50 nm. This punches are pressed onto different Cu alloys and Ni with grain sizes in between 100 µm down to the nanocrystalline regime. The nanoscale surface structures where analysed with a confocal laser microscope with regard to extrusion height and mould filling. In the presentation, the flow mechanism will be discussed at different length scales, where it is found that both, the work hardening behaviour and the grain size influence the structure formation on the nanoscale.