Experimental research on the polished surface quality of hard anodized film of aluminum alloy

Abstract

 An experimental study was conducted for the surface polishing of the oxide film after hard anodizing of 2D70 aluminum alloy. The surface roughness and surface morphology of aluminum alloy before, after anodizing and after polishing were analyzed, and the effects of polishing force, polishing speed, feeding amount and sandpaper grit on the polished surface roughness were investigated experimentally. The results showed that the surface roughness of 2D70 aluminum alloy decreased by 1 grade on average after hard anodizing. The hard anodized film surface has more linear protrusions, large pits and a large number of small pores. After polishing, the linear protrusions and small pores disappear, and a small number of new linear grooves appear, while the condition of large pits does not change much. The depth of small pores on the oxide film surface is within 11μm in most cases. As the polishing force, feeding amount and sandpaper grit increase, the decreasing trend of roughness value also gradually increases, and the decreasing trend of the thickness of hard anodic oxide film gradually increases. As the polishing speed increases, there is no clear trend in the decreasing trend of rough