Analysis of the Reasons for Aluminum Profile Mechanical Performance Failures and Solutions

Main reason analysis:

① The extrusion temperature of the aluminum profile is too low, and the extrusion speed is too slow. The temperature of the profile at the exit of the extruder does not reach the solution heat treatment temperature, so it cannot achieve solution strengthening.

② There are too few fans at the profile exit and the airflow is insufficient, causing slow cooling. This prevents the profile from dropping below 200℃ in the shortest time, causing coarse Mg2Si to precipitate prematurely, reducing the solution-phase content and affecting the mechanical properties of the profile after heat treatment.

③ The composition of the ingot is unqualified, and the Mg and Si content in the ingot does not meet the standard requirements.

④ The ingot was not homogenized, so the Mg2Si precipitates in the ingot structure cannot re-dissolve in the short extrusion time, resulting in insufficient solution and affecting product performance.

⑤ The aging process is improper, the hot air circulation is not smooth, or the thermocouple is incorrectly positioned, leading to insufficient or over-aging.

Solutions:

① Properly control the extrusion temperature and speed so that the profile's temperature at the extruder outlet stays above the minimum solution temperature;

② Enhance air cooling conditions. Factories that can, may install mist cooling devices to meet the minimum cooling gradient requirements for 6063 alloy;

③ Strengthen quality management of the cast ingots;

④ Perform homogenization treatment on the cast ingots;

⑤ Reasonably determine the aging process, correctly install thermocouples, and properly place the profiles to ensure smooth hot air circulation. Dimensional deviations.