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Leadfree Trials

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Leadfree Trials | 5 September, 2005


I would like to find out what trials everyone is carrying out when evaluating Leadfree Paste.



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Bob R.


Leadfree Trials | 6 September, 2005

We approached it the same way we select SnPb pastes. We started by doing coupon level tests to sort out the obvious "bad" pastes: SIR, wetting, solder balling, print quality, etc. That cut the field in half. From there we started to do assembly level testing with a board layed out with a variety of component types. We evaluated the pastes based on fillet quality, process window (some pastes had worse performance at the extremes of reflow profile window or printer settings), and defects (bridging, solderballing, etc). At the end we created a matrix and ranked each paste by its performance on each test. We gave each test a weighting factor then multiplied this factor by the rank and added them up. The paste with the best score won. There's some subjectivity in the weighting factors, obviously.

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Leadfree Trials | 6 September, 2005

Would it be possible to get a copy of the results?

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RoHS Ron


Leadfree Trials | 6 September, 2005

Hey Bob,

Why don't you toss us your DFM manual, customer list and financials while you're at it:)

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Leadfree Trials | 7 September, 2005

were looking at paste, wire, preforms and solder bars (for solder pots), concentraiting on HMP, sn62,96S, and 2 different sac alloys, we also have 7 different fluxes and 16 temination inks (which were also having to change for RoHS because the ink contains 0.5%Cd. were a little different from most of you guys due to the products we manufacture so my main hurdles to jump over are leaching and cracking of the ceramic substrates due to increased heat/ surface tension. processes covered are, soldering irons, heat guns,reflow ovens,hot plates, solderbaths and one or two others. and carrying out full qual testing, everything from salt spray,altitude, shock and vibrate life cycleing, micro sectioning ect.

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Leadfree Trials | 24 May, 2006

Saw that u have been doing testing with lead free.. Is it possible to have the resault of ur testing...

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Leadfree Trials | 25 May, 2006

in addition to all the test make sure you looking at voiding too...

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