plating, anodizing, & finishing Q&As since 1989
Why the chromate conversion failure in 168 hrs salt spray
June 30, 2010
why the chromate conversion coating failure in 168 hr salt spray?Chandramanipg Chandramanipg
manager in plating - Bangalore, Karnataka, India
First of two simultaneous responses -- July 6, 2010
There are any number of reasons and they cover the entire range from the parent material to the pre process to the process to the post process to the actual salt spray cabinet/material/operator.
Read some of the old posts at this site, on this subject. If you are using old (6 months or so) test panels, switch to new ones and the problem will probably go away.
Parts that have been "polished" with a steel rotary brush will probably never pass.
- Navarre, Florida
Second of two simultaneous responses -- July 7, 2010
We need much more detail before anyone can consider giving you an answer. You need to tell us what your process is, step by step, what your analysis control is like and whether there have been any anomalies, what you were testing to, the test conditions (did they meet specification requirements?), what materials you are treating
(are they castings, extrusions, machined parts?).
The above information I would consider to be a minimum to get any sense from us mere mortals.
Aerospace - Yeovil, Somerset, UK