A mechanics prediction of the behaviour of mono-crystalline silicon under nano-indentation

This paper uses a new constitutive model developed recently by the authors to analyse the multi-phase transformations in mono-crystalline silicon when subjected to nano-indentation. The finite element method is employed to the integration of the stress–strain relationship. A very good agreement is reached with the experimental measurements, with an accurate prediction of the observed pop-in and pop-out and detailed phase transformation events in loading and unloading. It was found that due to the change of microstructures, the material in the deformation zone could experience a local unloading during indentation loading or undergo a local loading during indentation unloading. The phase transformation events during indentation are closely related to the variation of both the deviatoric and hydrostatic stress components.