Abstract: This paper is mainly regarding to the structure and performance changes of automobile air filter and its two different stage of filtration material before filtration and after filtration. The purpose of experiment is to research the influence of impurity particles on filtration property. Firstly collected a group of same automobile air filter from market and taken off the filtration material, then adopted SEM、FT-IR、DTA and TG to analyze the internal structure, respectively. Meanwhile, other instruments were applied to characterize the performance change of this two different filtration material, for instance, the weight, thickness, air permeability, breaking strength and elongation, average pore diameter, maximum pore diameter, filtration accuracy and the changes of flow and pressure drop. The results show that there is an obvious difference between structure and performance of the new filtration material and second-hand material. The deposition of impurity particles on internal pore space surface pore space of filtration material has an important influence on internal structure, physical property and filtration property. And base on these results, we developed the new filtration materials and to make a deep comparison of filtration properties among them.

Key words: automobile air filter, filtration material, structure, physical property