Multiaxial stress-strain transfer across indenter-sample interface during in-situ indentation of soft high-entropy shape memory alloys and h

Nanoindentation is routinely used to determine local mechanical properties of materials like Young’s modulus, hardness and fracture toughness. Currently, however, the models for the evaluation of the load-deflection curves suppose the application of infinitely stiff diamond indenter tip and neglect its elasto-plastic deformation. The aim of this proposal is to perform in-situ experiments using a custom micro-mechanical system developed for ID13, which will be equipped with a dedicated wedge tip. The in-situ scanning experiments on soft and hard samples thin films will be used to assess both (i) the stress-strain evolution across the samples under the indenter and, additionally, (ii) the stress-strain evolution across the wedge indenter tip. The experiment will be used to enhance the understanding of the elasto-plastic deformation in the indenter-sample system and, additionally, to refine the finite-element models used for the evaluation of indentation experiments.