Mark, Does anyone on this forum know of current scientific work ongoing concerning the "total environmental impacts of solder substitutes"? I pulled up the methodolgy of the Stuttgart study, and am chasing down the author of the 2003-2005 US EPA funded study at the University of Tennessee. Seems to me with one of the focus areas of the proposed "Manhattan Project" to solve the lead-free dilema for the US Dept of Defense, that we are being very short sighted to choose an alloy based only on metallurgical properties. You are correct in assessing the trace addtives (let alone the impurities) in the new lead-free solders. After tin, silver, and copper, various suppliers are intentionally adding nickel, antimony, bismuth, zinc, germanium, indium, manganese, cerium, yttrium, titanium. How can we as scientists accept adding these to solder without considering the total environmental impact of the mining, smelting, operator exposure, and recovery operations of all these elements? Who has data? Who is willing to help take/compile data? So far, I have considered this a personal agenda, but am looking for a group of "concerned scientists/engineers/environmentalists" to gather data to keep some sanity in these deliberatoins. Denny Fritz SAIC, Inc - Subcontract to Crane Naval Depot. ________________________________ From: tinwhiskers-bounce@xxxxxxxxxxxxx on behalf of Mark Vaughan Sent: Fri 2/20/2009 3:19 AM To: tinwhiskers@xxxxxxxxxxxxx Subject: [tinwhiskers] Re: - RoHS & BGAs!!! The EU banned our lead in solder after people mainly children in countries like Africa, and India were being poisoned using fires to extract the lead from scrap electronics. At least the big publicity stunt to gain public support in favour of lead free was to film these children. I wonder how antimony is going to effect this. As far as I recall if you over heat it you get Stibium oxide which is another nasty poison. Not sure though whether it will form if an alloy is over heated. Just wait for it to be on the next ban list. Regs Mark Dr. Mark Vaughan Ph'D., B.Eng. M0VAU Managing Director Vaughan Industries Ltd., reg in UK no 2561068 Water Care Technology Ltd, reg in UK no 4129351 Addr Unit3, Sydney House, Blackwater, Truro, Cornwall, TR4 8HH UK. Phone/Fax 44 (0) 1872 561288 RSGB DRM111 (Cornwall) -----Original Message----- From: tinwhiskers-bounce@xxxxxxxxxxxxx [mailto:tinwhiskers-bounce@xxxxxxxxxxxxx] On Behalf Of Parnagian, Edward Sent: 19 February 2009 23:20 To: tinwhiskers@xxxxxxxxxxxxx Subject: [tinwhiskers] Re: - RoHS & BGAs!!! Thank you, Stephan! Quite frankly, I've been so concerned about whiskers, brittleness and cleanliness issues that tin plague has fallen below my radar. I really was unaware of the effects of antimony on tin plague. Best regards, Ed -----Original Message----- From: tinwhiskers-bounce@xxxxxxxxxxxxx [mailto:tinwhiskers-bounce@xxxxxxxxxxxxx] On Behalf Of Meschter, Stephan J (US SSA) Sent: 2009 Feb 19 8:45 AM To: tinwhiskers@xxxxxxxxxxxxx Subject: [tinwhiskers] Re: - RoHS & BGAs!!! If you are setting up equipment in Alaska subject to prolonged periods of continuous cold, you may want to consider the Lead-free AIM Castin alloy since it contains antimony, known to prevent tin pest. There has been some work showing that the impurities in current Lead-free solder are enough to suppress pest for most normal applications, however, each situation should be considered individually (D. Hillman SMTA 2007 and 2008). If you haven't already looked at them, you may also find info in the GEIA-STD-0005-1, GEIA-STD-0005-2, GEIA-STD-0005-3, GEIA-HB-0005-1, GEIA-HB-0005-2, and GEIA-HB-0005-3 useful. In addition to reliability, they capture many other aspects of lead-free such as program management, rework and repair, configuration management, supplier flow down, logistics, etc. They are a rapidly evolving document set, because lead-free information is changing so quickly. But they are our documents, to use and to shape as we see fit. Good luck, Stephan Meschter (older files in the thread deleted)