lead free board/chem-film chassis corrosion
lead free board/chem-film chassis corrosion
(OP)
We recently had an electronics box go through saltfog testing. It is a vented enclosure so during the test the corrosive atmosphere was present inside the box. There was significant corrosion where the board mounts to the aluminum chassis. The chassis is chromate, class 3 (low elec resistance). Any thoughts as to correcting this issue? We obviously can't just paint it since it is a ground path for EMI suppression and conduction cooling.





RE: lead free board/chem-film chassis corrosion
RE: lead free board/chem-film chassis corrosion
RE: lead free board/chem-film chassis corrosion
Zinc electroplating on aluminium is not likely to work.
RE: lead free board/chem-film chassis corrosion
RE: lead free board/chem-film chassis corrosion
RE: lead free board/chem-film chassis corrosion
Board is gold(IAW B48896G) over low stress nickel plate (AMS-QQ-N-290)
RE: lead free board/chem-film chassis corrosion
KENAT,
Have you reminded yourself of FAQ731-376: Eng-Tips.com Forum Policies recently, or taken a look at posting policies: http://eng-tips.com/market.cfm?
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: lead free board/chem-film chassis corrosion
RE: lead free board/chem-film chassis corrosion
On the limited salt spray testing I've done it can be tricky trying to work out visually what is aluminum oxide and what may be condensed salt.
KENAT,
Have you reminded yourself of FAQ731-376: Eng-Tips.com Forum Policies recently, or taken a look at posting policies: http://eng-tips.com/market.cfm?
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: lead free board/chem-film chassis corrosion
I can't think of a great solution. Perhaps you can isolate the aluminium electrically from the gold/nickel with a thermally conductive ceramic?