Causes of surface defects in aluminum profiles
Layering is an extrusion defect with no fixed distribution law. Most of them are discontinuous circular or curved thin layers distributed on the edge of industrial aluminum profiles, and obvious shell-like delamination can be seen. The main reason for the shell layer is that the surface of the ingot is stained with oil, dust, or the working part of the front end of the extrusion barrel is worn out, causing the accumulation of dirty metal around the front end elastic region. When extruded, it is formed by being rolled around the industrial aluminum profile along the sliding surface of the elastic zone. It usually appears at the end of industrial aluminum profiles. In severe cases, it may also appear in the middle section of industrial aluminum profiles, or even the front section. Also, the arrangement of the die holes is unreasonable, and the inner wall of the extrusion cylinder is too close and the extrusion cylinder, the pressing pad is excessively worn or deformed, and the like may also be layered.