Observation of viscoelastic displacement recovery after microindentation

Abstract

This paper reports on the time-dependent recovery process in a local part of a quasi-homogeneous and quasi-isotropic viscoelastic hemisphere after microindentation unloading. After contact between a Vickers indenter and a viscoelastic material comes to an end, the recovery progression is monitored using a microscope equipped with an interferometer, and a record is made using a digital camera. The histories of the depth of the indentation and the changes in the indented area are defined. Using an approach involving direct microindentation measurements of viscoelastic properties, the viscoelastic recovery creep compliance is determined and its values are compared with the creep compliance measured by the standard macro creep method, and with the creep compliance derived from instrumented microindentation.