Regensburg 2007 – scientific programme

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MM: Fachverband Metall- und Materialphysik

MM 14: SYM Micro- and Nanomechanics II

MM 14.1: Invited Talk

Tuesday, March 27, 2007, 10:15–10:45, H16

Micromechanics inside the SEM — •Benedikt Moser — Empa, Materials Science and Technology, 3602 Thun, Switzerland

A large variety of in-situ mechanical experiments have been developed over the last 10 years in a number of research institutes. Many of those experiments can be performed inside the scanning electron microscope, some of them even in the transmission electron microscope (JMR (2005) July issue). These techniques offer a wealth of new information on small scale deformation mechanics to the scientists and may avoid some measurement artefacts in difficult experiments by visual control. In this presentation the author will discuss two examples of in-situ micromechanical experiments based on a custom-built micro-indentation apparatus adapted to a standard scanning electron microscope.

The first part will discuss the in-situ indentation of a metallic glass. Here the formation of shear bands is observed in the SEM during the indentation process and is correlated to the appearance of displacement bursts in the load-displacement curve. The effect of varying deformation rates on the formation of shear bands is also investigated.

The second part will show the potential of the same apparatus to perform micropillar-compression experiments on the example of micromachined Si-pillars. It will be shown that by in-situ SEM-observations distinct deformation mechanisms can be seen: the diameter of the pillars has a clear influence on the failure mode and can be correlated to the Weibull distribution of strength.