Effects of Indenter Tilt on Nanoindentation Results of Fused Silica: an Investigation by Finite Element Analysis

In reality, it is a common phenomenon to perform nanoindentation test while the indenter is not perpendicular to the sample, which would cause the properties such as hardness and elastic modulus of sample to be somehow different from the true values. In this paper, the effects of indenter tilt on the results of nanoindentation were studied by finite element analysis (FEA) simulation. The results were compared with indenter perpendicularly penetrating into a flat surface. Conclusions show that when the tilt indenter penetrates into specimen, the projected contact area varies widely. The tilt indentation could significantly influence the tendency of the force-displacement curves, and could also affect the hardness and elastic modulus of the specimen that obtained from the results. Finally, a simple method is given to correct the values of projected area, hardness and elastic modulus once tilt indentation happens.