Lead-Free Solder Bar

Hi,

All your ideas regarding the above content is welcom!!!

Kindly help me ...

Advance Thanks for your help..

Hari

Hello haricool:

can you try a new solder pot, and get your own test done on the piece you solder from it? It may be a worker has put a different type of solder in the pot you are using? It may also be that your supplier has given the wrong solder to you?

What do you think?

Most likely it's not the pot. There could be traces of lead in the wire that are leeching out during tinning. Also have you solder analyzed by your supplier. I just had it done for $85.00us. You may want to have an independent lab analyze a finished part if this is a real problem with your customer.

Be sure to buy RoHS compliant materials!

Hello DGCYS:

You said what I said but it is still good advice! A GA on its way.

If the solder pot was not properly cleaned before you swithced to Pb free solder, your mixture purity would be compromised. Also, be certain that the Pb-free solder you are using is what it says on the label. If anyone is using the solder pot to strip and re-tin product already coated with Pb containing solder, the pot contents will become contaminated. I suggest you have a sample from the pot analyzed. Finally, remember that some copper alloys contain Pb for machinability. If you are using one of those alloys, your product will fail regardless of your pot purity.

Hello welderman,

You mentioned some detail I mentioned also. But added other detail. If mixed solder types are used, it is so easy to screw thing up. I only ever had this problem at home but, then went over to entirely PB free dolder. I realise it may not be possible to do this in industry, but, they should put the solder to be used with each pot, on a shelf by that pot.

A GA is on its way.

I think you should find out what analytical technique was used to determine that the lead content was above 1000 ppm. If the solder is a two-phase alloy (usually the case for solder) and X-Ray Florescence was used to determine the composition, then a major error could have resulted. I would recommend that a wet technique be used. I have personally seen errors as high as 20 % that resulted from using XRF on two-phase solder alloys. An alloy must be homogeneous before the XRF method can be used. If both labs used a wet technique, ask both of them to perform a recheck.

Bill Morrow

Hi bmorrow492:

Yeah, I've also thinks in a same way but i've not that much information/evidence to prove it.

Are u saying that XRF technique will more precise(to find out the composition) rather than other techniques.

If yes, then the path is open for a soultion. Since our customer tested the solder(SAC 305) using XRF technique but our supplier as well as we tested the samples using ICP (Inductive coupled plasma) technique.

But still i've one more crisis, In XRF technique the lead ppm found to lie around 7000~10000ppm & the same found to be 500 ~600 ppm in ICP technique.

Can you conclude that above difference will be digestible w.r.t the both technique.

And also if you any articles/evidences,etc. , (that technique will also have a vital role in testing) pls send me to close the issue.

Thanks for your help.

Hari

Any textbook on XRF analysis will tell you that, in order to obtain an accurate analysis, the sample must be homogeneous down to about 50 to 100 microns. The solders I have had the opportunity to work with are two-phase alloys, and not adequately homogeneous for XRF. I can't predict what, if any errors would be encountered on your sample be cause 1) I don't know if it is a two-phase alloy and 2) if it is two-phase I don't know the spacial distribution of the elements. Just to be safe, I would use a spectroscopic method (AA, ICP, etc).

Bill Morrow