Study On Characterization Of Wear Surface Morphology Of Rubber Composites

Wear is one of important performance index of the many rubber products,especially tire, directly affects the safety and life of products. And wear performanceis closely related to wear surface morphology. Wear surface morphology is the finaldirect recording of the process of friction and wear, which is the most direct and maincriterion determining the wear mechanism. The characteristics and variation of wearsurface morphology is important parameter to reflect the wear condition. Study onidentification and evaluation on the wear surface morphology can be used tocharacterize the wear performance of rubber composites.Based on gray-scale images photoed by confocal laser scanning microscope ofWear surface of rubber composites, the fractal theory and wavelet theory is applied tostudy on the wear surface morphology.The main work is as follows:(1) Discrete Fractal Brownian Incremental Random (DFBIR) is introduced to thestudy of wear surface morphology of rubber composites. The combination of fractalparameter Hurst (H) with surface gradient (b) realize to classification andcomprehensive evaluation of wear surface morphology of rubber composites.(2) The fractal dimension D is calculated with Differential Box Counting (DBC)on the basis of gray-scale images of wear surface morphology of rubber composites,which illustrates that fractal dimension D can characterize the overall roughness ofwear surface morphology of rubber composites. At the same time, the fractal featuresof wear surface morphology of rubber composites and relations between H and D isverified.(3) The multi-fractal theory is used to analyze the local features of wear surfacemorphology of rubber composites. Characterization parameters of multifractal spectrum of surface morphology is established. The multifractal spectrum Δα is morewide, height distribution of wear surface is more uneven. If the spectrum difference ofthe multi-fractal spectrum Δf is negative, the surface morphology is mainly “peak”and the altitude is higher. On the other hand, the surface morphology is mainly“valley”, and the altitude is lower. The combination of spectrum width Δα andspectrum difference Δf can more accuratly analyze the height distribution from thewhole to the local on the surface morphology, and realize the quantitativecomparison on the height distribution of different surface morphology of rubbercomposites.(4) Wavelet theory is applied to study the changing law of the wear surfacemorphology of rubber composites. By the wavelet decomposition of gray image ofwear surface, the energy distribution ratio of each sub-image after waveletdecomposition is regarded as the change basis of the texture of roughness in differentdirections. And the distribution ratio of energy of the sub-image is calculated.The reliability and availability of the results is verified according to thecomparison between The above results and3D image of the wear surfacemorphology captured by confocal laser scanning microscopy.