How to distinguish the quality of aluminum foil?

In the production process of aluminum foil, multiple processes such as rolling, finishing, annealing, and packaging are required, and the production process is interconnected. Any problem in any link may lead to quality issues with the aluminum foil. The quality defects in the purchased aluminum foil products not only affect their appearance, but also directly affect the quality of the produced products. Moreover, they can directly cause the aluminum foil to break and shut down, greatly affecting production efficiency. How to distinguish the quality of aluminum foil?

Based on the experience of aluminum industry professionals, distinguishing the quality of aluminum foil can mostly be directly detected with your "keen eye". However, to distinguish the quality of aluminum foil, we should first understand the common quality defects of aluminum foil. Only by having a clear understanding of them and then comparing them with common quality problems can we prevent aluminum foil with quality defects from being stored in the warehouse.

Today, Xiaohui has compiled the most comprehensive aluminum foil quality defect problems in history, and attached high-definition large images of the problem aluminum foil. After we buy the aluminum foil, as long as we diagnose the problem once for this batch of aluminum foil, we can naturally determine whether the quality is good or bad!

1. Aluminum foil damage
Aluminum foil collision refers to the damage caused to the surface or end face of the foil material after colliding with other objects during transportation or storage. Most cases of scratches are caused by carelessness during aluminum foil packaging.

2. Corrosion
The defects generated on the surface of aluminum foil after chemical or electrochemical reactions occur when it comes into contact with surrounding media. The corroded aluminum foil surface will lose its luster, and in severe cases, gray corrosion products may also be produced. The corroded aluminum foil will have a significant impact on the aesthetics of the products produced at the end.

3. Surface bubbles
Aluminum foil with surface bubble defects will have irregular circular or strip-shaped cavity protrusions on its surface; The raised edges are smooth, asymmetrical on both sides, and the distribution is irregular. Surface bubbles cause uneven stress at various points of the aluminum foil strip, which is likely to lead to pulling and stopping.

4. Dark stripes
Dark stripes mostly appear on double products, with obvious bright and dark striped patterns along the rolling direction, which affects aesthetics.

5. Imprints
There are various situations that can cause imprints on the surface of aluminum foil, such as defects or dirt such as metal shavings on the surface of the rolling or guide rollers, unclean or locally smooth protrusions on the surface of the sleeve or core, or foreign objects sticking to the surface of the foil during coiling, etc. The surface of foil with imprints generally has single or periodic depressions or protrusions, which are easy to distinguish.

6. Oil stains
The common oil stains on aluminum foil are formed after annealing and generally appear as light yellow, brown, and yellow brown spots.

7. Poor oil removal
To check whether the degreasing is clean, the degreasing level is usually tested by brushing water after annealing. If it does not reach the level specified in the brushing water test, there may be oil on the aluminum foil.

8. Crack edge
The phenomenon of longitudinal edge cracking on the surface of aluminum foil is called edge cracking. In severe cases, obvious gaps can be seen at the edges.

9. Poor board shape
Due to uneven deformation, there are local undulations on the surface of the foil material