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Testing And Simulation Of The Multi-Layer's Tribological Characteristics

Posted on:2005-10-13Degree:MasterType:Thesis
Country:ChinaCandidate:Y ZhouFull Text:PDF
GTID:2121360122496610Subject:Carrier Engineering
Abstract/Summary:PDF Full Text Request
Preparing thin solid film on the metal surface is one of the important methods to improve the metal properties. The multi-layers, especially the gradient layers, can greatly improve the stress and strain distributions near the interfaces between the coating and substrate and between the layers, so that it can prevent the coating from cracks and spalling from the substrate. The Finite Element Analysis program has been developed and the Finite Element Analysis Method has been applied in this paper to calculate the stress distributions in the layers. The main conclusions of this paper are:(1) The planar elastic Finite Element Analysis program has been developed under Visual C++6.0. The program has been divided into several module and each of them were encapsulated into the classes. Consequently, the program's structure is clear and easy to debug; the program can solve the problem of elastic contact and its boundary condition is easy to modify. The pre-processing program and post-processing program can be used to other FEM program with little change.(2) The effects of the film properties on the stress distributions of the layers especially near the interfaces have been analyzed. The main results are: There is a optimal thickness of the layer for a constant load, otherwise the shear stress on the surface may decrease; with the increase of the elastic modulus, the shear stress on the surface may also increase while that of interfaces lies on the difference of elastic modulus between the coating and the substrate; the shear stress near the interfaces will decrease if the number of layers increase; with the increase of the friction coefficient the stress near the interfaces will increase at the foreside of contact zone while it will decrease at the tail of the contact zone.(3) The tribological characteristics of Cu, Ni and Cu/Ni coatings have been analysised by use of FEM. The effects show that the multi-layer can improve the condition of the stress distributions near the surface. As a result, the condition of stress distributions of the substrate can be improved.The results of this paper can be the guideline of preparing multi-lays. At the same time, some basal researches have been done for the purpose of combining the Molecule Dynamic Analysis and Finite Element Analysis to test and simulate the tribological characteristics of the multi-layer. As it's just some exploring researches we still have a long way to run in the future.This thesis has been supported by National Science Foundation (Approval No. 50071014) of China.
Keywords/Search Tags:Multi-layer, Finite Element Analysis, Object Oriented, Stress Distribution
PDF Full Text Request
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