Mechanical response of multilayers submitted to in-situ experiments

A variety of different degradation mechanisms of multilayers deposited on a substrate, can be observed and analysed when performing a mechanical test in a Scanning Electron Microscope (SEM). Tensile experiments were performed in a SEM on multilayered systems consisting by amorphous and/or metallic layers deposited on metallic substrates. From the experiments and accounting of analytical models several critical parameters related to the observed mechanisms can be deduced. The different steps of the mechanical response is then characterized. As expected, damage follows cracking of the layers, then debonding. By the comparison of the experimental results, it is noted that the characteristics of cracking is strongly dependent of the behaviour of interfaces in a layered system.