Nano-sclerometry measurements of superhard materials and diamond hardness using scanning force microscope with the ultrahard fullerite C₆₀ tip

The new procedure for the hardness measurements of superhard materials including diamond using the scanning force microscope with the ultrahard fullerite C₆₀ tip was developed. It is shown that diamond is plastically deformed under the indentation by the ultrahard fullerite indenter at room temperature. Now the correct measurements of diamond hardness have become possible. The hardness values measured are 137 ± 6 and 167 ± 5 GPa for the diamond faces (100) and (111), respectively.