Aloha, fun & authoritative answers -- no cost, no registration, no passwords, no popups
(as an eBay Partner & Amazon Affiliate we earn from qualifying purchases)

Where the
world gathers for metal finishing
Q&As since 1989

-----

copper sulphate test for zinc phosphate quality

2003

In a discussion with an engineer at Ford about my zinc phosphate pretreatment, he asked me if I had ever heard of using copper sulphate [on eBay or Amazon]to test for the amount of zinc phosphate coverage. He indicated that he has seen it done, but didn't really know the particulars.

The general idea is that the CuSO4 "sticks" to the areas where the zinc phosphate crystal is not (we are treating SAE 9254 steel by the way). I read through most of the posts on CuSO4 plating on this forum, but I could not discern a method that I should try.

Most of the posts I read complained of the copper not sticking to the steel after it was rinsed with water. I probably don't care if this happens as I do not need a permanent coating here. I just want a nice visual way to tell if I am getting a decent zinc phosphate coverage.

I do look at my parts under the SEM from time to time and the coating varies depending on where I look. So I'm curious if there is a macro type test to check that out.

Any ideas on a method I should take a run at?

David Taylor
automotive suspension components - Florence, Kentucky, USA

(No "dead threads" here! If this page isn't currently on the Hotline your Q, A, or Comment will restore it)

Q, A, or Comment on THIS thread -or- Start a NEW Thread

Disclaimer: It's not possible to fully diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations might be harmful.

If you are seeking a product or service related to metal finishing, please check these Directories: