G. S. Smith, E. B. Tadmor, N. Bernstein and E. Kaxiras
Acta Materialia, 49, 4089–4101 (2001).
Nanoindentation experiments are an excellent probe of micromechanical
properties, but their interpretation is complicated by the multiple length
scales involved. We report simulations of silicon nanoindentation, based on
an extended version of the local quasicontinuum model, capable of handling
complex crystal structures, This method embeds an interatomic force law within
a finite element framework. We identify which features of the simulation are
robust by investigating the effect of different interatomic force laws and
different finite element meshes. We find that our simulations qualitatively
reproduce the experimental load vs. displacement curves of indented silicon
and provide information on the microscopic aspects of the phase trans
formations that take place during indentation. This information is linked
to the macroscopic electrical resistance, providing a simple physical
picture that gives a satisfactory explanation of experimental results.