Nickel Plating and RoHS requirement

A. Your supplier is spot on. Under Annex of Directive 2002/95/EC " Applications of lead, mercury, cadmium, hexavalent chromium, which are exempted from the requirements of Article 4(1), item 6 reads...."Lead as an alloying element in steel containing up to 0.35% lead by weight, aluminium containing up to 0.4% lead by weight, and as copper alloy containing up to 4% lead by weight".

A. The question is if the part is considered homogeneous with the plating or not if I understand you correctly.

I would say NO. Whether or not the alloy can contain % of lead has nothing to do with the coating applied. The coating must be compliant on its own merit to meet RoHS standards.

I agree with you, Bill. As an aside, the galvanizer's association doesn't, as mentioned in letter 40864. I think the galvanizers association will learn that they were wrong. Ted Mooney, P.E. Striving to live Aloha finishing.com - Pine Beach, New Jersey 2006

A. It seems to me that if the plating were considered homogenous with the base part no one would be worried about Hexavalent chrome passivation on a steel zinc plated machine screw, or the amount of Cadmium in an electroless Nickel plated standoff.

A. The component is not RoHS compliant as the plating is not homogeneous, i.e., can be mechanically disjointed.

Thanks Ralph!

All: When Humpty Dumpty spouts nonsense in a debate, and Alice tries to explain that words must have consistent meanings, he tells Alice: "When I use a word, it means just what I choose it to mean -- neither more nor less".

And so it is with the RoHS language...

Although any school child can easily separate the chromate from the zinc plating with the eraser end of an old pencil stub... and although a skilled machinist can't remove the zinc plating from an object with a diamond-turned superalloy chisel, RoHS rules consider the chromate "homogeneous" to the plating, and the plating "not homogeneous" to the part -- because that's what they want it to mean.

Yes, they've attached a ludicrous meaning to the word "homogeneous", turned it on its head like Humpty Dumpty -- but that's just the way it is. And Bill, Douglas, and Ralph are correct!

Regards,

A. Hi Ted,

Different people can have different ideas on what a word means that is why in the standard this is defined:
Definition:
'homogeneous material' means one material of uniform composition throughout or a material, consisting of a combination of materials, that cannot be disjointed or separated into different materials by mechanical actions such as unscrewing, cutting, crushing, grinding and abrasive processes.

Took me a long time to get my head around that one!

Thanks again, Ralph; you're absolutely right that the plating is not 'homogeneous' to the component by that definition. My issue is that, per that same definition, the chromate conversion coating is absolutely not homogeneous with the plating. But what can I do but accept that Humpty Dumpty is the boss of me? :-)

Luck & Regards,

A. Exemption 6C applies to lead in copper alloys.
www.getenviropass.com/rohs-exemptions-6/

And some finishes may be under an EU RoHS exemption.

A. Hi Devandra.
I take it, your question '% correct for RoHS' to mean 'is this % RoHS compliant'. At 2.92% lead, the brass is certainly RoHS compliant.
Since brass is an alloy of copper, under Annex of Directive 2002/95/EC " Applications of lead, mercury, cadmium, hexavalent chromium, which are exempted from the requirements of Article 4(1), item 6 reads...."Lead as an alloying element in steel containing up to 0.35% lead by weight, aluminium containing up to 0.4% lead by weight, and as copper alloy containing up to 4% lead by weight".

A. Hi Donie. We appended your inquiry to a thread which at least partially answers it, and implies that you may need to get further data. Good luck.

Regards,

A. Hi Donie.
As Ted suggested, need more info.
1. what type brass material?
2. what type of nickel plating?

Cheah

A. Hi Donie.

C3600 free cutting brass has a lead content of 2.5~3.7%.
This is well below the 4% maximum limit set for RoHS under Annex of Directive 2002/95/EC. You are RoHS compliant if C3600 material is used in your product.
Good Luck.

Cheah

A. I think that the issue is not fully understood here.
Or maybe I mix a few terms.
If we are dealing with bathroom fittings, there is a problem with the water quality because of the lead in the brass.
The inside of the fitting is NOT plated with nickel and the water that comes out of this fitting is leaching lead and we DRINK it.
So, the requirement in this case is not ROHS but NSF61.
Nowadays all bathroom fitting made of brass have to be leached in special fluoride-containing solutions to leach the lead out of the brass.
BUT in 2014 or so, new regulations are coming up and manufacturers will be forced not to use lead-bearing brass.