Mechanical Property Analysis of Micro-Contact Resistance of Surface Coating

Mechanical property of coating under the micro-contact load such as impact and sliding wear significantly influence the reliability of surface coating. In order to research the influence, a contact model between the rigid multi-asperity surface and coating was found based on the G-W model in the background of Thermal Barrier Coatings(TBCs) used in aircraft engine blade. The distribution of stress in subsurface of the micro-contact process was analyzed based on the theories of contact mechanics and tribology with the elasto-plastic finite element method. The effect of coating thickness, elastic modulus, yield strength on the distribution of residual stress for TBCs was investigated. It conclude that primary reason of coating failure are cumulation of plastic deformation and excessive interfacial stress. The results are significant for studying the life and final spallation of TBC system and other coating.