Effect of Surface Texture on Asperity Flattening at Plastic Deformed Interface in Static Contact State

doi:10.3901/JME.2016.03.093

Abstract

Abstract: The effect of surface texture on asperity flattening at plastic deformed interface in static contact state has been investigated experimentally. Two types of surfaces textures of specimens, isotropic surface and solely directional surface, are obtained by polishing. A series of compression tests are carried out with lubricant and without lubricant respectively using HDM-20 End-Face Tribometer. The three dimensional surface topography of the specimens are observed by means of JM-6200 optical microscope. The three dimensional surface parameters are measured with Talysurf CCI Lite. The variations of surface microstructure are analyzed by choosing such parameters as Sa, Sal, Str, Sdr and Sdq. The experimental results show that the surface texture of specimens has a significant effect on asperity flattening. The isotropic surface exhibits a higher rate of asperity flattening than the solely directional surface without lubricant, while an opposite situation occurs with lubricant. The effect of surface texture on asperity flattening leads to regular changes of the three dimensional surface parameters. Based on mechanical-rheological model, it comes to a conclusion that the effect of surface texture on asperity flattening with lubricant can be attributed to the presence of closed lubricant pockets, which is validated by the extraction of the closed lubricant pocket features.

Key words: asperity flattening, closed lubricant pocket, real contact area ratio, surface topography, texture

CLC Number:

TH117

HU Zhaowen, LIU Kun, LIU Xiaojun, WANG Wei. Effect of Surface Texture on Asperity Flattening at Plastic Deformed Interface in Static Contact State[J]. Journal of Mechanical Engineering, 2016, 52(3): 93-100.

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