Pick Up Effects on Al Extrusion

[seerix]

Dear Expert Friends,

Some of our products, have pick up marks(defects) on them. We're observing pick-up effects during and after the extrusion process. I'm trying to solve this problem so I'm open for ideas and tips.

Thanks

 

[TVP]

Can you provide some additional details on the exact nature of these defects? Size, location, etc.? Die construction, materials, heat treatment, surface treatment, etc.? The following has some descriptions of defects:

http://faculty.kfupm.edu.sa/coe/sadiq/proceedings/SEC2002/vol5/P137.pdf

Two other recent contributions on defects in Al extrusions were authored by Alcan and the University of Queensland:

Classification of Streaking Defects on Anodized Aluminium Extrusions

http://www.scientific.net/MSF.618-619.349

Effect of primary intermetallic particles on surface microstructure and appearance of aluminium extrusions

http://www.sciencedirect.com/scienc...serid=10&md5=58a143d2bf29536d5d73dead3f35d917