Effects of Proximity on Hardness and Elastic Modulus Measurements of SiO2 and Cu by Nanoindentation

The effects of distance between two indentation points in the measurements of hardness and elastic modulus by the nanoindentation technique were assessed. Silicon Oxide (SiO2) and Cu were used to represent the nanoindentation behavior of brittle and ductile material, respectively. The distance between two indentation points was varied from being sufficiently far apart to being almost adjacent to the boundary of the neighboring indentation mark. Contrary to common understanding, it was discovered that proximity between indentation points had almost no effect on the hardness and elastic modulus measurements. Finite element method simulations were also performed to understand and verify the experimental results.