Improvement of instrumented indentation test accuracy by data augmentation with electrical contact resistance

Abstract

Instrumented Indentation Test allows thorough surface multi-scale mechanical characterisation by depth-sensing the indenter penetration and correlating it with the indenter-sample contact area and the applied force. Localised plastic phenomena at the indentation edge, i.e. pile-up and sink-in, may bias the characterisation results. Current approaches attempt correcting related systematic errors by numerical simulation and AFM-based techniques. However, they require careful tuning and complex and expensive experimental procedures. This work proposes a methodology based on in-situ Electric Contact Resistance which augments information on the contact area and allows edge effect correction. The methodology is demonstrated and validated on industrially relevant metallic materials.