基于分形理论的纳米Si3N4/PTFE复合材料磨损性能分析

he wear properties of PTFE composites filled with nano-Si3N4 were investigated with M-2000 wear tester. The worn surfaces of PTFE composites were examined through a scanning electric microscope (SEM). The micro cracks of the worn surface were filtered and its fractal dimension was calculated using MATLAB image extraction tool. It was found that the addition of nano- Si3N4 increased the wear resistance for PTFE and the nano-Al2O3 mixed with nano- Si3N4 enhanced the wear resistant performance largely for PTFE, and the rate of abrasion decreased largely. The nano-particles take the role of supporting, and they could prevent the generation of abraded cracks. The worn surface of PTFE composites had obvious fractal characteristics. The fractal dimension of worn surface for the composites corresponded with its wear mass loss and the fractal dimension had the same changing tendency with wear mass loss.