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Scratch resistance of dyed aluminum anodizing

2004

I am making a buckle from anodized aluminum and dyed in various colors. The buckle is used for cargo tie downs with nylon webbing so its going to be subject to fairly heavy use. I would like to know what the process would be to ensure a product that is both strong and scratch resistant. Can I get away with using standard anodizing process (Type II) as good colors are important or is it better to go the hardcoat process? I want to maintain the aesthetic finish of the product as long as possible. Does Type II or Type III anodizing make any difference to the longevity of the colors?

Any advice appreciated

Thanks

Liam Kiggen
- Cape Town, Western Cape, South Africa

Only you and you customer can decide what is "best". One option that you did not mention is a poor man's hardcoat which is at a higher temp than a true hardcoat with a bath additive. It is not as durable as a true 32F hardcoat, but it is better than type II for wear and will still take a decent dye. Another option that will take some trial and error testing is just dropping a type II tank to 65F and anodizing to a final 24 volts. This will give a harder and thicker type II coating that will take dye virtually the same as a regular type II.

James Watts
- Navarre, Florida
2004