Three-dimensional finite element analysis of thin films cracking along ceramic substrates

In the present work, three-dimensional finite element method is used to calculate the J integral and the size of plastic zone at the interfacial crack tip of ductile films bonded to a ceramic substrate in mode I. The effects of the specimen thickness and the crack length on the variation of the J integral and the size of the plastic zone at the crack tip were highlighted. The J integral and the plastic zones were computed in the surface and the middle of the film/substrate composite.

► The thickness of film has a very important effect in the mechanical resistance of film/substrate composite.
► Delamination of thin film is highly dependent on crack length.
► The distribution of the integral J along the crack front is symmetrical compared to its center.
► The equivalent stress exceeds largely the yield stress of the film.