This is a summary of my data for 10:1 pdms. It is a bit messy this way so i like to plot it as:
Which does better at capturing the essential behavior. Delaminations appear in thicker films, and as the film thickness increases eventually appear below the critical strain for buckling (i.e. in thick films you see only delaminations and no wrinkling). More notable is the 'localization'. This thing (illustrated below) appears in the thinnest films, and the strain at which they appear grows with film thickness. The physics behind these structures remains undetermined. Obviously it has to do with moving into a 'thin film' limit, but if they represent local plastic failure or a purely geometric effect remains to be answered.
Wow, that's an awesome image! Is that the step-wise ones that we often see in the thin films? I observe the same thing in terms of delamination: For really thick films, you don't see wrinkling and it goes straight to delamination. I need to go thinner on my films to observe similar effect as yours for the critical strain for the localization, I think.
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