Common defects of aluminum alloy extrusion profiles of type 6063 and their solutions

【China Aluminum Network】 6063 aluminum alloy profiles are widely used due to their many advantages such as good plasticity, moderate heat treatment strength, good welding performance, and gorgeous surface color after anodizing. However, in the production process, some defects often occur, resulting in low product quality, reduced product yields, increased production costs, and reduced efficiency. As a result, the company’s market competitiveness has decreased. Therefore, from the root cause to solve the 6063 aluminum extrusion profile defects is an important aspect of improving their own competitiveness. According to many years of aluminum production practice, the author summarized the common defects of 6063 aluminum alloy extrusions and their solutions, and communicated with many colleagues in order to promote each other.

1 Scratching, rubbing, bruising, scratching, and bumping are surface damages that occur when the profile exits the die hole and comes in contact with tools, equipment, etc. in subsequent processes.

1.1 Main Cause 1 Ingot surface has foreign matter or segregation of ingot components. When a large amount of segregated precipitates are present on the surface of the ingot and the ingot is not homogenized or homogenized, the ingot has a certain amount of hard metal particles, and the metal flows through the working belt during the extrusion process. These segregated precipitates or hard metal particles adhere to the surface of the working belt or cause damage to the working belt, resulting in scratches on the surface of the profile.

2 There are debris on the mold cavity or working belt, the hardness of the mold working belt is low, so that the work belt surface is injured when the extrusion and scratches the profile;

3 The exposed metal or graphite bars in the discharge track or oscillating plate have hard inclusions, which cause scratches on the surface of the profile when they come into contact with the profiles;

4 When the fork bar is sending the profile from the discharge rail to the swing bed, the profile is damaged due to excessive speed;

5 caused by artificial dragging profiles in the swing bed caused by scratches;

6 The friction or extrusion between the profiles causes damage during transport.

1.2 Solutions 1 Strengthen the control of the quality of the ingot;

2 to improve the quality of mold repair, the mold periodically nitrided and strictly enforce the nitriding process;

3 Use soft felt to separate the profiles from the auxiliary tools to minimize the contact damage between the profiles and the auxiliary tools;

4 Handle with care in production, try to avoid arbitrarily dragging or turning profiles;

5 Reasonably arrange the profiles in the material box to avoid friction with each other.

2. Unqualified mechanical properties 2.1. Main reasons 1 The temperature during extrusion is too low, and the extrusion speed is too slow. The extrusion temperature of the profile cannot reach the solution temperature, and solid solution strengthening is not achieved.