| PTFE has many excellent properties, such as: excellent self-lubrication, low friction, chemistry stabilization and thermal stabilization, but it has low mechanics characters and wear resistance. Many different kinds of fillers can improve its mechanics characters and wear resistance. In this paper, the wear and friction properties of PTFE filled with SiC and other inorganic-material has been studied. PTFE composite has obtained by mechanical mixture and compression molding. With MM-200 wear and friction tester, the wear mass loss and friction coefficient of PTFE composite in dry sliding has been evaluated. Scanning Electronic Microscopy (SEM) is used to describe the worn surface. The wear improve mechanism of different content and granularity of SiC is studied. In this paper, the fractal character of worn surface of PTFE composite is also studied. With the strong digital image tool module of MATLAB and fractal geometry method, the fractal dimension of PTFE composite worn surface is calculated, fractal dimension can describe the worn surface of PTFE composite.The result indicates that: SiC can improve wear resistance of PTFE, and wear mass loss of PTFE decrease with the increase of SiC, meanwhile the friction coefficient increase a little. PTFE filled with nano-SiC improve wear resistance much more than others. In the condition of this experiment, PTFE filled 7% nano-SiC have the best wear resistance. The worn surface of PTFE composite has obvious fractal character. The bigger fractal dimension is, the more serious worn surface is. Fractal dimension can describe the wear mass loss of PTFE composite.
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