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Atomic Force Microscope Nanoindentation/Scratching. Nanoindentation/Scratching. Elastic & plastic material properties are obtained from load-displacement data, but knowledge of the true area of contact is critical. sink-in. Load (µN). Stiffness, S:. (nm). pile-up.
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Nanoindentation/Scratching Elastic & plastic material properties are obtained from load-displacement data, but knowledge of the true area of contact is critical. sink-in Load (µN) Stiffness, S: (nm) pile-up
Indentation is Possible With F/D Curves Tip moving in Tip moving out C D A F B E B A C F E D
AFM Nanoindenting Problems With AFM:a) The probe geometry (area) is not know, not quantitative b) The probe motion is not horizontal at contact.
AFM Scratching When Scratching With the AFM, there is a torsion on the cantilever so the probe area changes.
Nanoindentation Characterization The AFM is ideal for characterizing nanoindents and nano scratches in a surface. AFM Image of nanoindents in a surface.
Summary • All AFM instruments can create nanoindents and nanoscratches in a surface. • The technique is not quantitative because the probe/surface angle is not characterized • The AFM is useful for characterizing nanoindents and nanoscratches.