The onset of plasticity in Au(111) was analyzed at the atomic scale. Images of dislocation traces and other features obtained by atomic force microscopy around nano-indentations were correlated with force vs penetration curves obtained in the same experiment. It was demonstrated that the discontinuities in force vs penetration curves were associated to the generation and glide of dislocation loops with well-characterized parameters. Half loops intersecting the surface, with screw components, were recognized and processes of cross-slip identified. The formation of terraces and permanent traces around the nano-indentation points was explained in terms of the elastic theory of dislocations in a continuum.

Dislocation Mechanisms in the First Stage of Plasticity of Nano-Indented Au(111) Surfaces. A.Asenjo, M.Jaafar, E.Carrasco, J.M.Rojo: Physical Review B, 2006, 73[7], 075431 (7pp)