Nanoindentation of heterogeneous carbonaceous films containing Ni nano-crystals.

Composite films of nano-size nickel grains embedded in a carbonaceous matrix are synthesized by a PVD process of C(60) fullerenes and Ni acetate. The morphology of the nano-composite films is characterized by TEM, selected area electron diffraction, chemical analysis and AFM. Correlations with deposition parameters and typical structure changes are found. The mechanical properties are analyzed by nanoindentation. The load-displacement charts show typical pop-ins correlated with the heterogeneous nano-structure. The depth dependent hardness and indentation modulus vary according to the nano-composite structure and reflect the changes of the mechanical properties in the film.