Mode Dependent Toughness and the Delamination of Compressed Thin Films
نویسنده
چکیده
We consider the buckle-driven delamination of compressed thin lms. For a wide class of patterns of delamination, it is shown that the loading on the delamination front progressively goes from mode I to mode II during growth of the blister. As a result, the mode dependence of the lm/substrate interface excludes widespread delamination. This explains the observations of blisters of nite extent, which are otherwise diÆcult to interpret. We also study a model of interfacial fracture with friction. It reveals that a severe mode dependence can be induced by interfacial friction. This permits to account for the mode dependence, using only simple ingredients: friction and linear elasticity.
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