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Best Hard Anodize Solution

Sir,

I'm working with one of aerostructure company and currently I'm having big problem with hard anodize.After numbers of trials, the result still failed on salt spray test.The average maximum time before failed is 100++ hours but the requirement is 336 hrs.We passed all others test such as thickness, coating weight, microhardness and hardness.

Through initial investigation, we found a root caused due during seal with Deionised water.It prone to fail salt spray test at average 100++ hrs. However, if the specimens sealed with dichromate it shown good result.Dichromate application is not allowed in this case for process approval.

please Advise.

Helmy
Aerostructure - Melaka, Malaysia
2005

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2005

Try increasing the temperature and time in your DI seal bath.

Good luck.

Jim Gorsich
Compton, California, USA