Optimal indent spacing for instrumented nanoindentation of nanoporous gold

Improvements to nanoindentation techniques have enabled faster data acquisition and expanded data interpretation methods. Methods such as instrumented high-speed nanoindentation facilitate local mapping of nanomechanical properties. To create accurate maps, indent spacing should prevent previous indents from influencing subsequent indents. However, indents must be close enough to understand local property variations. The optimal ratio of indent spacing to indent depth (s/h_c) is well established for dense materials, but not for materials with nanoscale porosity. Nanoporous gold was tested at multiple s/h_c ratios, to identify optimal spacing for nanoporous structures. These are shown to have the same requirements as dense materials. Graphical abstract: (Figure presented.).