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-----Improve aluminum adhesion to polyester/epoxy resin
Quickstart:
Chromate Conversion Coating of Aluminum (Alodine, Iridite, Chem-Film) ⇦ huh? can improve the bondability of aluminum; but for the best adhesion, phosphoric acid anodizing is probably the ultimate. ASTM D3933 will probably prove very helpful.
Q. I am Terence SY Ong, the Manager of Chemical Engineering in Belton China. Our company is mainly manufacturing the hard disk component to Seagate and WD and most of the products are involving the bonding process with 6061Al. So I surf around the website and I am pleased that I can acquire this website for enquires. Since I am not the expert in this adhesive field, I would appreciate you can support me in some technical aspect about the bonding process.
Recently we find an occasionally drop off between the epoxy and the 6061 Al (300 dppm). The outlook for the drop off is there has no epoxy left on the 6061 Al surface. Of course, we do the surface finishing process on the Al surface with extensive aqueous cleaning w/ US in cleanroom before bonding process. Would appreciate you can provide some hints about this issue.
hard disk industry - Hong Kong
2007
by J. D. Minford
on Amazon or eBay
or AbeBooks
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A. I'm not sure I completely understand your question, but for what it is worth you can sometimes increase the adhesion of the epoxy to the anodize by making sure that your anodize wasn't sealed. Talk with your anodizer to smooth out the process.
Good luck!
Compton, California, USA
A. Terence,
Locate the work process sheet ('shop traveler') having signatures of production workers and inspectors. Follow the processing sequence and look for deviations from your company's procedures, the customer specifications and the epoxy product bulletin. Also, check expiration dates on the epoxy materials, chemical analysis records for process solutions, equipment calibrations, adhesion test records, worker training records, etc.
ASTM D2651, 'Standard Guide for Preparation of Metal Surfaces for Adhesive Bonding,' gives a number of aluminum pretreatments which may be helpful. After most pretreatments,* bonding should be performed within 1 hour of the final drying. *Except if sulfuric acid anodized (unsealed), for which the time limit is 72 hours.
Pretreatment of aluminum by phosphoric acid anodizing (unsealed) is described in ASTM D3933-98,
'Standard Guide for Preparation of Aluminum Surfaces for Structural Adhesives Bonding (Phosphoric Acid Anodizing).'
- Goleta, California
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Multiple threads merged: please forgive chronology errors and repetition 🙂
Q. Sir I am a final year student of materials engineering.
In my final year project, I am facing the main hurdle about the adhesion problem of aluminum foil of about 0.1- 0.2 mm and polyester/epoxy resin. I have tried a method of scratching off an oxide surface of aluminum by sandpaper but no satisfactory result is achieved. Kindly suggest me a solution.
student - Karachi, Pakistan
May 27, 2010
A. I would try chem film (chromate conversion) with products like Alodine or Iridite.
James Watts- Navarre, Florida
A. Since you are a student I will give you a reference to get out of the library and reference in your thesis.
ASM Engineered Materials Handbook Vol 3.
Section on Surface Preparation of Metals
That should give you enough ideas to be going on with and a reference to show where you got it from and your literature search
Aerospace - South Wales, United Kingdom
A. Hi Zeeshan,
You may also wish to look into phosphoric acid anodizing to promote adhesion. I think if you search the site with search terms like "phosphoric acid anodize adhesive bonding ASTM D3933" you will find lots of good info right here on finishing.com, but you can also use the same search term on google..
Luck & Regards,
Ted Mooney, P.E. RET
Striving to live Aloha
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