Indentation Load-Displacement Relations for the Spherical Indentation of Elastic Film/Substrate Structures

摘要

The spherical indentation of elastic film /substrate structures is analyzed using the finite element method. The load-displacement curves of the film /substrate structures of various configurations are obtained and analyzed, A generalized power law relation is established, which can be used to analyze the load-displacement curve of elastic film /substrate systems under spherical indentations. The indentation load is dependent on the modulus ratio of the film to the substrate and film thickness. A semi-analytical expression for the power of the power law relation is also obtained as a function of the normalized film thickness and normalized film modulus, which can be used to determine the modulus of the film from a spherical indentation test.