Novel Analysis on the Influence of Tip Radius and Shape of the Nanoindenter on the Hardness of Materials

Nanoindentation is a powerful technique used for assessing mechanical properties at nano/micro-scale. It is used for obtaining material parameters like elastic modulus, hardness, plastic or viscous parameters from experimental readings of indenter load and depth of penetration. Forces involved are usually in the milli or micronewton range and the depth in the order of nanometers. Different kinds of probes can be used for making an imprint into the material surface. Very small material volumes having the order of several tens of nanometers can be accessed with the tip of the nanoindenter and material properties can be evaluated for such a small piece of the materials. Nanoindentation finds application in extracting the elastic and plastic properties of the indented material surface. The effective knowledge of the indenter tip geometry is significant in nanoindentation experimental analysis. A small deviation from the ideal tip geometry affects the accuracy of the result during nanoindentation experiments. In the present investigation, we have studied the influence of tip radius of the indenter on the hardness of for different indenter shapes such as spherical, conical and Berkovich.