Main Causes of Surface Damage on Aluminum Profiles
① Foreign matter attached to the surface of the ingot or segregation of ingot components. When a large number of segregation protrusions exist on the ingot surface and the ingot has not undergone homogenization treatment, or the homogenization treatment is ineffective, a certain amount of hard metal particles remain inside the ingot. During the extrusion process, as the metal flows across the working belt, these segregation protrusions or hard metal particles attach to the surface of the working belt or cause damage to the belt, ultimately resulting in scratches on the surface of the profile.
② There are foreign objects on the mold cavity or the working belt. The working belt has relatively low hardness, causing the surface of the working belt to be damaged and scratch the profiles during pressing;
③ There are exposed metal or graphite strips with harder inclusions on the discharge track or swing bed, which can scratch the surface of the profiles upon contact;
④ When the fork rod transfers the profiles from the discharge track to the swing bed, the profiles can be damaged due to excessive speed;
⑤ Scratches are caused when profiles are manually dragged on the swing bed;
⑥ During transportation, profiles can be damaged due to mutual friction or compression.
Solution
① Strengthen the control of ingot quality;
② Improve mold repair quality, regularly nitride molds, and strictly follow the nitriding process;
③ Use soft felt to separate the profile from auxiliary tools, minimizing contact damage between the profile and auxiliary tools;
④ Handle with care during production, and try to avoid dragging or flipping the profiles casually;
⑤ Place profiles reasonably in the material frame, and try to avoid friction between them.
