An uncertainty-based quality evaluation tool for nanoindentation systems

Instrumented Indentation Test (IIT) is a nonconventional mechanical tests allowing multi-scale mechanical characterisation. It is employed for research and quality control in strategic manufacturing fields for developing edge technologies. The state-of-the-art lacks a robust methodology to assess quality of indentations and benchmark indentation devices. This is limiting the application of IIT for specifying and verifying tolerances. This work proposes an uncertainty-based quality evaluation tool for IIT. A non-parametric uncertainty evaluation of calibration contribution is proposed. The method shows the statistical significance of indentation sets modelled by the bootstrap samples. The uncertainty is then propagated according to the law of uncertainty propagation for the evaluation of mechanical characteristics. The methodology is applied to five case studies. Results show that the uncertainty evaluation model can achieve robust and sensitive quantification of the indentation results and system quality, thus providing a useful practical tool for industrial and academic practitioners within a metrological framework.