Salt Spray Testing of ZAMAK plated with Nickel-Chrome

Q. Dear Sridhar,
Thanks for your response.
We are intending to use ZAMAK #3, and they are intended to be Barrel plated.
The end use is a cubic pivot part used for riveting the cover of water cycle suite in the toilet.
The kind of test we need is a test that we can frequently run in the factory.

TUTORIAL FOR NEWBIES:

Zamac is a family of alloys with a base metal of zinc and alloying elements of aluminium, magnesium, and copper

Zamac

Salt spray / salt fog is a popular accelerated testing procedure, and is most often conducted in accord with ASTM B117. However, there are many tweaks to the test or alternatives to it which some feel are more representative for particular substrates, coatings, or circumstances and CASS (copper accelerated salt spray) is one such.

Still, accelerated testing is only a QA test to help insure that the quality of processing has not deteriorated, it is not a predictor of real life because the conditions are very different. For example, in real life the corrosion products of certain coatings are glassy and impervious and greatly slow corrosion, whereas these corrosion products do not form in the test chamber.

In rack plating, individual pieces to be plated are hung on 'racks', which is easy to picture. In barrel plating, a large group of relatively small parts is put into a special perforated plastic barrel and treated in mass. See our library article on Barrel Plating.