OS06W0407 Mechanical testing of materials in small volumes by nanoindentation and microbeam bending

Abstract

In this work, we compare experimental results of mechanical testing, i.e. nanoindentation and microbeam deflection, on metal thin films on substrates. For these techniques, however, the required sample geometry, loading and straining conditions are quite different, and as a result, comparisons between the different techniques are difficult. It will be shown that a detailed computational analysis is required to identify material parameters such as yield strength and hardening modulus for the thin film materials. In particular, the use of neural networks to facilitate the analysis of plastic behavior is discussed. For both types of experiments, the general trend has been confirmed that the yield strength of thin metal films increases with decreasing film thickness. However, a detailed comparison of the deformation behavior shows significant differences between the different testing techniques.