Identification of a soft matrix-hard inclusion material by indentation

A new procedure for identifying the mechanical behavior of individual phases within a bi-material (matrixparticles) is presented. The case of AlSi10Mg (large globularized Si-rich particles surrounded by an alpha-Al phase) processed by additive manufacturing and post-treated is taken as a typical example. Grids of nano-indentation tests are performed at different locations on the nanocomposite using a Berkovich indenter and show an impact of the hard inclusions on the experimental curves. The elastoplastic properties of the matrix are identified based on the lowest load-indentation depth curves. Several representative finite element (FE) models demonstrate the influence of the particles on the nano-indentation response. The capacity of the FE model to predict the indentation curve of a cube corner indenter experiment and the Berkovich grid result scattering was checked. A representative volume element (RVE) based on a scanning electron microscope (SEM) image is defined. The identified material parameters of the alpha-Al phase and Si phase, it allows the prediction of the stress-strain curve of a macroscopic experimental tensile test.

Automated summary

A new procedure for identifying the mechanical behavior of individual phases within a bi-material is presented. The influence of hard inclusions on the material properties is studied using nano-indentation tests and finite element models, and a representative volume element (RVE) is defined. This method can be used to predict the mechanical properties of macroscopic experiments.