| Search our quarter-million Q&As |
Home of the finishing HOTLINE since 1989
-----Conversion coating for high pH (cow manure) protection
Q. We have an electronic product that has a plastic case, with very pure aluminum deposited
on the inside for shielding purposes. It is top coated with Sanchem Safegard CC-3400 Seal #2
which is excellent for salt corrosion (our product is also used in marine environment).
I testing, I find that cow manure etches thru the conversion coating and aluminum to the plastic.
Have any of you used a topcoat that is able to withstand the high pH (~11)
I have been told that nickel may stand up better in our environment.
Thanks for your recommendation.
Patrick
product designer - Loveland, Colorado, USA
March 24, 2011
A. Hi Patrick
Indeed aluminum is amphoteric, dissolving in alkali as well as acid. Nickel is far more corrosion resistant than aluminum. If it is practical to electroless nickel plate your boxes, and if it delivers the shielding you are looking for, it sounds like the robust solution.
Luck & Regards,
Ted Mooney, P.E. RET
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
Need quick confidential answers? $25
Need project assistance? $100/hr.
Sorry! Finishing.com is temporarily Read-Only.
Ted Mooney is retiring but I have several offers to take it over.
We're working hard to make sure we find it the best new home.