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Sn99 Cu0.7 Ag 0.3


Rob

#33065

Sn99 Cu0.7 Ag 0.3 | 7 March, 2005

Hi does anyone have any experience of running Sn 99 Cu0.7 Ag 0.3 solder in their waves? Also is there any reliabilty data available? I think it may also be called C7A3.

All I can find is a brief mention in a table in IEC 61190-1-3 2004, and on a previous thread by Greg York.

I've met a number of Blundell CMS400 users recently looking at this alloy, and it appears to be a great deal cheaper than the heavier Silver compositions - under 1/2 the price, and appears to promise improved solderability on Sn/Cu.

Cheers,

Rob.

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KEN

#33084

Sn99 Cu0.7 Ag 0.3 | 7 March, 2005

Here are some general rules for lead free wave solder:

Noble aloys will cost more. Period. The cheapest metal on earth is lead. Costs can only go up in Lead Free.

Consumer grade and class 2 electronics will most likely use Tin / Copper for wave. Why? Cost vs. performance.

Hi-rel assemblies add 3-4% silver.

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KEN

#33085

Sn99 Cu0.7 Ag 0.3 | 7 March, 2005

Oh silver and its...improved solderability over tin / copper. BS if you ask me. Look to your flux and thermal profile for wetting spread. Ask yourself just how much "wetting spread" do you need to fill a barrel?

I have the same 100% barrel fill on Immersion silver boards as with multi thermal-excursion ENTEK (which in my opinion is the most difficult to process). Oh and this without nitrogen.

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py (france)

#33093

Sn99 Cu0.7 Ag 0.3 | 8 March, 2005

a french subcontractor had tried this alloy for a show (in france). I was here , the PCB was not to hard to weld , but the results were not as good than Sn63pb37.(of course) the advantage is the price. see cookson for details.....

This message was posted Add this forum to your site! Click to learn more. the Electronics Forum @

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Rob

#33122

Sn99 Cu0.7 Ag 0.3 | 10 March, 2005

Thanks for your help, & will look into Cookson as soon as http://www.alpha-frytechnologies.com is working again.

Cheers,

Rob.

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#33129

Sn99 Cu0.7 Ag 0.3 | 10 March, 2005


Rob

#33133

Sn99 Cu0.7 Ag 0.3 | 10 March, 2005

Hi Jerry,

Thanks for the info - it's very helpful. I'm assuming (as it carefully refrains from saying it anywhere!) that SAXC0307 is Sn99/Cu0.7/Ag0.3.

Cheers,

Rob.

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greg york

#33806

Sn99 Cu0.7 Ag 0.3 | 20 April, 2005

With twenty five machines working with the LFB227/S on our little island it does seem to work well. Wetting is good compared to Tin/Copper and flow is comparable to 63/37. Biggest problem sticking 3 - 4 % Ag in a solder ignoring the patents and royalty nightmare scenario is the dross these alloys produce. We calculated the other day one customer alone threw away 26p (thats 49c to you guys) of Lead Free high silver content solder per board. This just simply does not happen with 0.3Ag alloy if manufactured correctly.

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#33850

Sn99 Cu0.7 Ag 0.3 | 22 April, 2005

Ken Which flux are you using

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