Finite Element Simulation On The Mechanical Properties Of The Film/Substrate System In The Process Of Nanoindentation

As a kind of surface technology,film/substrate system used in several engineering field is developed quickly and widely. There is a remarkable difference of the mechanical properties between films and bulk materials, which have the same chemical composition. We can establish a sound strength theory, life theory and failure criteria to the structure from the research on that. This not only take a key part in the development of film material, optimization of film productive process, overall performance upgrade of film/substrate system and the design of film/substrate morphology, but also have an important role in promoting the fundamental, deep-seated study of mechanical properties of low dimensional materials.Firstly, This study measured the modulus and hardness of the film of Titanium Nitride thin film / High-Speed steel substrate by nanoindentation experiment, and get the load - displacement curve; Sencodly,the process of the Berkovich indenter's 120nm press-into the thin film was simulated through the finite element analysis, and we got the specific form of relationship of dimensionless function by treating the results; Thirdly, the yield limit of Titanium Nitride film is calculated with the load - displacement curve and the specific form of relationship of dimensionless function combined. Fourthly, the influence of the film thickness on the stress distribution of Titanium Nitride thin film / High-Speed steel substrate was analyzed from the shallow and deep indentation by the modulus and yield strength gotted through the nanoindentation experiment and Dimensional analysis. Finally, attempt to do the 3D finite element simualtion of the process of indentation by DEFROM-3D, and got the effictive stress distribution and the effictive strain distribution which was relatively similar with the result of 2D finite element simualtion.