Printed Circuit Board Assembly & PCB Design SMT Electronics Assembly Manufacturing Forum

Printed Circuit Board Assembly & PCB Design Forum

SMT electronics assembly manufacturing forum.

XRF absolute necessity??

Views: 2613


XRF absolute necessity?? | 12 January, 2006

Hi all, while looking at some XRF equipment, a question arose as to the need for testing lead-free components at the CEM facility.....if a CEM has RoHS compliancy certificates from component vendors, is that "Due diligent enough" to absolve the CEM of liability if a leaded component (with a RoHS compliant certificate from the vendor) gets put on a lead-free board and then audited?

the above question is from a non-process perspective (of course you would want to know if you have leaded balls in a BGA but has a RoHS compliant certificate from the vendor)


reply »



XRF absolute necessity?? | 13 January, 2006

As long as you trust that the component vendor is honest & diligent (possibly add this to your vendor rating criterea?)

In the UK we have a 'RoHS Trusted' Kitemark from the British Standards institute that distributors can apply for to show this. I'm guessing that there is an equivilent in Europe & the US.

The main thing that you may have to worry about is the hard to find parts that your Purchasing Department bring in from brokers, that may not have the facilities to verify the status of grey market parts.

reply »



XRF absolute necessity?? | 25 January, 2006

I agree Rob,

The main thing is that you don't beleive everything without question. If you're sure the supplier knows what he's doing and you have a good relationship with him then a declaration should be OK. When doubt arises it is worth getting samples analysed. An XRF is a good piece of equipment but I would suggest using a "RoHS Screening" lab as you will need a certain amount of knowledge & experience to get the most out of it.

I should stress that, generally, the concern is more to do with the other 5 substances as suppliers generally know if there is Pb in the terminations.

FYI the RoHS Trusted Kitemark ( is available elsewhere... not just Europe.

reply »



XRF absolute necessity?? | 30 January, 2006

we shouldnt be talking about lead free we should be talking in terms of RoHS compliant. HMP solder is exempt in the directive even though it has a hig lead content (93.5%) as no other alloy will melt at the same temperatures 298. as HMP is exempt withing the directive, some suppliers are classing product built with HMP as RoHS compliant (it meets the directive). now we get to the problem, if the hmp joint on the component happens to form the area where the component is to be soldered to the PCB, for example during the assembly of the component the whole assay is diped in HMP coating the leads/pads, When it is sold as a component it will be ROHS compliant when the hmp is then soldered to with SAC during assembly to the PCB the lead content will be lowered to less then 85% within the joint creating a non RoHS compliant pcb assembly. I dont imagin this to happen frequently but i came across one SMT component where it did. so look at your components closly and if needed buy an XRF.

reply »



XRF absolute necessity?? | 30 January, 2006

True, we weren't just checking for lead at the test lab we were also checking for banned substances in the plastics - PBB's & PBDE's which apparently appear a lot in the recycled plastics used in manufacturing connector bodies; & also the other banned metals: Cadmium, Mercury, & Hexavalent Chromium.

reply »



XRF absolute necessity?? | 2 June, 2006

Do not believe every thing your suppliers tell you, even a written cert does not guaranty compliance. We recently purchased a Niton XRF analyzer. The first day in use we found component�s that were made for us "RoHS" that were far from compliant. People make mistakes, in this case and employee mistakenly filled their solder pot with Lead. 60000 parts were rejected. Ouch! And we have found other parts in our � RoHS inventory�. Think about the cost, even if your vendor is ultimately responsible. Contamination in your wave solder is quite costly to eliminate. More over.. when will you know it is contaminated? Rework of contaminated products�good luck!

Ultimately it�s your Customer that�s important. How will they react when your product is held up in Customs and ultimately returns to sit in your warehouse? Who pays for it?

reply »

Industry 4.0 Reflow Oven

Online IPC Training & Certification