The Study Of The Debond And Buckling Of Soft Substrate Interlayer Film

With the development of technology,the application of membrane materials is becoming wider,such as aerospace,optics and micro electrical.Membranes will be damaged due to the influence of external load in complex engineering situation.The failure modes,including film fracture,delamination and buckling shorten the life of film.Studies of soft substrate interlayer film show that the interlayer film will affect the properties of a thin film system.Thus studying the effect of the transition layer on the film base system will be beneficial.In this thesis,the interfacial properties and mechanical properties of the films with interlayer film are studied by experimental and numerical analysis.Based on the buckling and debonding of the film under compressive stress,the interfacial properties and mechanical properties of the films were studied.At the same time,the effect of residual stress on debonding was investigated.Experimental study of the metal film with transition layer was carried out.The metal film and the aluminum interlayer film were deposited on the substrate by magnetron sputtering method.The two types of specimens were tested in the single axis compression loading device.The formation and propagation of linear buckling of thin film were observed.And then the film was unloaded,and the linear buckling mode of the unloading process was observed,which was transformed to the linear buckling of the telephone.Based on the theory the instability of Euler of thin film,the theory model was established to solve the energy release rate during the SSIF debonding and buckling.Normalized energy release rate of SSIF was calculated numerically and the regularity was explored based on the experimental data.Then the law of stress transfer and the solution of shear stress on the surface of the SSIF under compression load conditions were analyzed.Residual stress can induce film spontaneous debonding and interface cracks due to its biaxial states.Normalized energy release rate of film debonding was solved through a theoretical model created in this thesis.The effects of film material parameters and film thickness on the normalized energy release rate were discussed.The study on the buckling of the transition layer thin film provides a technique and method for investigating the mechanical properties of the transition layer films.