Nanoindentation experiments with small tip radii: an experimental method

Nanoindentation experiments were performed with spherical tip radii on one ceramic and three metals. The resulting Young´s modulus appears to be lower than expected values. The method and analytical approach are then discussed. In particular, the shape of the indenter, the contact between the tip and the surface, and pile-up effects have been studied. Finally an approach is proposed in order to differentiate plastic materials from each other by evaluating the contact topology between the tip and the surface.