Nanoindentation of a Layered Crystal Structure Oxide

Nanoindentation was performed on layered structure materials to determine values for stiffness and hardness perpendicular to the layers. In order to establish the validity of this technique for anisotropic materials, layered minerals with known elastic constants were tested, including brucite and muscovite mica. A layered ceramic oxide of interest, KCa 2 Nb 3 O 10 , was also investigated. A Berkovich diamond tip was used to carry out the indentations. Indents were made on atomically flat surfaces of crystals, as observed in-situ with an atomic force microscope. Analysis of load versus displacement data showed that the elastic constant C 33 for muscovite and brucite agreed to within five percent of literature values. In the case of KCa 2 Nb 3 O 10 , average values of 57.0 GPa for C 33 and 3.8 GPa hardness were obtained.