Multiscale modelling of nanoindentation test in copper crystal

The nanoindentation test in the dislocation free crystal of copper is simulated by a nonlinear elastic finite element analysis coupled with both ab initio calculations of the ideal shear strength and crystallographic considerations. The onset of microplasticity, associated with the pop-in effect identified in experimental nanoindentation tests (creation of first dislocations), is assumed to be related to the moment of achieving the value of the ideal shear strength for the copper crystal. Calculated values of the critical indentation depth lie within the range of experimentally observed pop-ins in the copper crystal. The related indentation load is somewhat lower than that observed in the experiment.