Quasi-static and dynamic depth-sensing indentation measurements to characterize wear and mar resistance of coating–polymer systems

Abstract

Abstract Different layers of different thicknesses were coated on the same polymethyl methacrylate (PMMA) substrate. For each of these bilayered systems, quasi-static and dynamic instrumented indentations using continuous stiffness measurement have been made. We verified if data from indentation tests performed on a given sample obey a power law relationship. The aim was to calculate the viscoplasticity index n with sufficient accuracy (by taking into account the viscoelastoplastic properties of the studied samples), since this value is characteristic of the viscoplastic properties of a material and, therefore, allows evaluating the plastic scratch resistance of the surface. Thanks to both indentation methods the viscoplasticity index could be calculated and its value compared to the different bilayered systems one. As n is supposed to be intrinsic to a material, its value should not depend on the characterization technique.