due to their commonly non-conductive nature. Additi- ally they might be damaged by the electron beam of the microscope or the vacuum might cause outgasing of solvents or evaporation of water and thus change material properties. Furthermore, for all kinds of materials a considerable amount of expe- mental effort is necessary to build a tensile testing machine that ts into the chamber. Therefore, a very promising alternative to SEM is based on the use of an atomic force microscope (AFM) to observe in situ surface deformation processes during straining of a specimen. First steps towards this goal were shown in the 1990s in [1-4] but none of these approaches truly was a microtensile test with sample thicknesses in the range of micrometers. To the authors' knowledge, this was shown for the rst time by Hild et al. in [5]. 16.