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Salt Spray Test Exposure Calculation

2006

We are doing salt spray test as per ASTM B117 (5% NaCl sol.)for Anodized aluminium specimens for aerospace industries. The exposure time as per standard varies from 168 hrs. to 500 hrs depending on the process type.

ASTM suggests continuous wet cye for the specified time. We would like to know, is it permitted if the cycle is interrupted (switch off the facility for 24-30 hrs), keeping the specimens in the salt spray chamber and restart the facility later. The exposure time will be considered for chamber "SWITCH ON" condition only.

What will be the effect on the results.
Request clarification.
Biren desai
Godrej & Boyce, Mfg. - Mumbai, Maharashtra, India

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Biren -

There are chambers and test routines for doing wet/dry cycling experiments. But generally I would say that anodized aluminum is supposed to stay wet the entire time with only very short interruptions just to open the lid briefly. Allowing your specimens to completely dry is not something I would recommend.
Terry Tomt
- Auburn, Washington
2006

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Dear Sir

I work in Metal finishing lab and face the problem of interrupted Salt Spray Test.

Salt Spray Test some time gets interrupted due to power failure or at the week ends. Is it possible to continue the test. If interruption is longer ( Week ends)can the test specimen be removed rinsed dried and then reloaded while the test starts again.

If components are allowed to be kept in test chamber over week end and test continued when the work starts again on monday. Is there any guideline possible for accounting this idle period.

Kindly, favour me with your views on the issue.
Vijay Sane.
Metal Finishing Chemist. - Mumbai, India
2007