What about the blistering on the extruded surface of aluminium sheet?
In the extrusion process of aluminium sheet, surface peeling or bubbles are very likely to occur. What is the cause? What method should be used to eliminate it? Now it's up to the aluminium plate manufacturer to dispel your disagreement and solve your confusion for you! ________
What is bubbles or peeling: Bubbles with convex shape appear on the surface of the product, which are common in the head and tail. The complete bubbles are called bubbles, and the cracked ones are called peeling.
1. Causes of bubble and peeling in aluminium sheet extrusion
1. The abrasion of the extrusion cylinder and the extrusion pad is excessive, the dimension of the extrusion cylinder and the extrusion pad is not matched properly, and the diameter difference of the gasket used exceeds the allowable value.
2. Extrusion cylinder and cushion are too dirty, sticky with oil, moisture, graphite, etc.
3. Lubricating oil contains water;
4. The ingot surface has too many troughs, too deep, or there are air holes and sand holes on the ingot surface, loose structure, oil stain and so on.
5. When the alloy is replaced, the cylinder is not cleaned up.
6. Extrusion cylinder temperature and extrusion ingot temperature are too high.
7. The temperature and size of ingot exceed the allowable negative deviation.
8. The ingot is too long, fills too fast, the ingot temperature is uneven, which causes non-drum filling, so the exhaust in the barrel is incomplete, or the operation is inappropriate, and the exhaust process is not carried out.
9. The die hole design is unreasonable or the cutting residue is improper. The residue in the shunt hole and the diversion hole is partially taken out, and the gas in the space enters the surface during extrusion.
2. Elimination of Bubbles and Peeling in Aluminum Plate Extrusion
1. Reasonably design the matching size of extrusion cylinder and gasket, check the tool size regularly to ensure that it meets the requirements, and repair the big belly of extrusion cylinder in time, so that the gasket can not exceed the tolerance.
2. Keep the surface of tools and ingots clean, smooth and dry.
3. When replacing the alloy, the cylinder should be cleaned thoroughly.
4. Check equipment and instruments frequently to prevent excessive temperature and speed.
5. Strict implementation of process regulations and systems;
6. Reasonable design and manufacture of tools and dies, diversion holes and diversion holes are designed into 1-3 degrees of inclination;
Strict operation, correct cutting of residue and complete exhaust.
Through the answers and answers of experts, we believe that we have a deep understanding of the causes of bubble and peeling in aluminium sheet extrusion and the elimination methods. To avoid these problems in daily production, we can reduce the loss and improve the yield.