Abstract: in this paper some experimental results including author and coworkers in this field aresummarized. It is focus in the following topics: (1) deformation field of interfacial layer and interfaciallayer model; (2) stress concentration and singularities near the interfacial edge of bimaterials; (3)relax of the interfacial stresses and functionally graded materials; (4) interfacial fracture mechanics.