Chrome Plating standard. 2

[ssummers]

Does anyone have a standard for testing Chrome Plating. Our incoming inspection was strictly visual. We ran into a problem where we received parts that looked good on the outside, but were actually double plated where the Chrome plating peeled right off. We found the problem out when we had to do some resize a hole. I am an Industrial Engineer striving to proactively push our Q.C. and Engineering Departments.

Since this problem occurred, we changed our paint adhesion specification to be simply an adhesion specification that now covers our painted parts and the Chrome plated parts. This specification requires our parts to pass a tape test. This is a the test where 2 lines are scratched through the coating in a criss-cross pattern. If the tape pulls up the coating, the part is bad.

My questions are as follows:
Are there any other standards which we should consider?
Are there any other testing methods worth investigating? Non-destructive? [sig][/sig]

 

[rembrandt]

I dont relly expect you to gain anything from your adhesion test. There are gauges available on the market, (Try Elcometer, Droylsden, Manchester, England for instance)
They will be able to supply you with a Dry Film Thickness Gauge, they can supply for non magnetic coatings (Chrome For Instance,) on a magnetic substrate.
Hope this helps you.

 

[jmnspec]

A customer has asked for an acid test to determine if a shaft is chrome plated. He said you put the acid on the shaft and it will change color (yellow or green). Can anyone help me with this?

joen@jmnspecialties.com

 

[dgallagher]

I'd be interested in knowing what it is that you are plating - is this a shaft journal area?

 

[damc]

a solution of copper sulphate will turn bare steel a brownish coler. It is a good test to see if chrome plating has been ground thru to base metal. It will not determine if the coating is chrome or something else.