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Lead free in hirel

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#60918

Lead free in hirel | 25 January, 2010

This is a post from another forum as a response from Bob Landman to a claim that he had no evidence to be concerned about lead-free in hirel applications (interesting read). See below and am sure many technetters will find this interesting ***************************************************************************************

Here's a partial list of problems ignored by the EU and major manufacturers as they have switched to lead-free manufacturing to comply with the EU lead ban.

PREFACE:

The waivers for defense and high rel products are essentially useless (unless one sends parts to a replater to dip them in molten lead) as the major component vendors have rushed to embrace lead-free manufacturing. They have, in many cases, mixed their lead and lead-free parts by using the same part numbers for both. They have refused to make available to RoHS exempt industries lead bearing platings on components.

1) Microsoft's XBOX as has been widely discussed on this and other forums

2) increased number of failures in recently purchased PC products

3) subject matter experts of published environmental tests show increased amounts of failures in lead-free manufacturing (mechanical connection failures) including parts popping off boards, voids in BGA balls, etc... Manufacturers continue to state lead-free manufacturing is "ok", "no problems found"

4) Conformal coatings mitigate the growth of tin whiskers (and not using lead in solder guarantees that whiskers will grow) yet commercial product manufacturers (including a major telecom product provider who shall remain nameless) told me and several others on a teleconference that I attended on behalf of the Dept of Homeland Security, that "the selling price of the products cannot bear the cost adder of conformal coating".

5) Swatch watch company gets a waiver to use lead as millions of their watches fail due to tin whisker shorts on crystal oscillator

6) FDA forced Medtronic to recall their implanted cardiac defibrilators (from patients bodies) when whiskers shorted the devices. http://www.fda.gov/ora/inspect_ref/itg/itg42.html

7) a major Ethernet switch maker has senior field service personnel who have not been told of the potential for tin whisker growth so when failures happen, boards are simply replaced. Reason given is that "customers pay for service contracts so who cares what the reason is that they fail so long as we repair them quickly".

8) a major contract assembler states at a recent IEEE Reliability Society meeting that they see no problems with lead-free manufacturing yet an aside from one of their customers was said to me that "of course they don't see the problems, we see them AFTER we ship the product."

9) all the whisker failures reported here http://nepp.nasa.gov/WHISKER/failures/index.htm plus I am advised by NASA that they have confidentiality agreements with many others who call in to report problems which prevents them from listing the failures

10) I was recently at a national meeting on lead-free manufacturing where it was admitted that on many warplane systems there are lead-free manufacturing problems but the manufacturers refuse to go public with the information.

11) Anonymous (Terrestrial Application) - Field Failures First Observed Circa 2003 http://nepp.nasa.gov/WHISKER/anecdote/2003ckt_breaker/index.html

12) over 15,000 papers have been published on the subject of tin whiskers http://www.dbicorporation.com/rohsbib.htm yet to this day, no-one can state why they grow or how without lead to stop them, how quickly they grow, how long they will grow.

13) white paper by the AIA outlining the problems http://www.aia-aerospace.org/assets/wp_leadfree_0208.pdf

14) As was recently posted here by Denny Fritz:

A large amount of information has been accumulated in the Aerospace/Defense community about lead based versus lead-free solders/solder joints. A good place to start to tap this knowledge has recently been gathered at the Defense Acquisition University web site:

https://acc.dau.mil/leadfree

I will point out the second item on the list - the Lead-free Electronics "Manhattan Project" to compile the "best practices" for use of lead based or lead-free solder in harsh environements. 15 leading metallurgical scientists in the US met for two weeks to compile this 350 page baseline. Since then, the same 15 met again in August to outline the required research to close the knowledge gaps between leaded and lead-free solder, particularly in harsh environments.

15) The AIA and others are proposing to the US Dept of Defense a $95M project which will take three years and which will hopefully come up with solutions to the present problems with lead-free manufacturing.

The bottom line is, that util the problems outlined above are solved, if the EU does not want people to die from an increased amount of failures in transportation, electric power, medical devices, not to mention the waste and expense of filling landfills to overflowing with an increasing number of failed electronic products, the EU should immediately retract the RoHS ban on lead in manufacturing electronic assemblies and components and instead specify that at least 5% lead should be in all tin coatings and solders.

Bob Landman H&L Instruments, LLC

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#60922

Lead free in hirel | 26 January, 2010

Personally, I think that the EU got the order backwards with ROHS and WEEE. They should exempt Pb (in electronics) from ROHS until there is a comparable alternative, and enforce WEEE to keep consumer electronics from our landfills. But that's just me.

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#60939

Lead free in hirel | 26 January, 2010

Humm, a more logical solution, no wonder the politicians didn't think of it.

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Reflow Oven

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