Causes of surface peel of aluminum 6061 alloy tube

The surface peel of 6061 aluminum alloy tube occurred during turning. The surface peel area of aluminum alloy tube was studied by means of chemical composition analysis, scanning electron microscopy and energy spectrum analysis, and X-ray diffraction analysis. The results showed that there were a small amount of Al₂O₃, a small amount of SiO₂, MgO and other oxide inclusions and a small amount of refining agent residues in the surface peel area. This was because in the process of aluminum alloy smelting, the removal of impurity elements and inclusions was not sufficient, and the aggregation of inclusions such as Al₂O₃ existed at the peel area. The hardness of Al₂O₃ inclusions was higher than that of aluminum matrix,resulting in peeling phenomenon.