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Technology Science

Researchers Getting the Lead Out of Electronics 178

alphadogg writes "Researchers at the University of Maryland say they have discovered a material to replace lead, a potential environmental hazard, in electronics products. The material, bismuth samarium ferrite (BSFO), was found by researchers in the university's A. James Clark School of Engineering. It can be used in products such as biomedical imaging devices and inkjet printers, and if implemented commercially could keep lead out of landfills and the ecosystem, they say. While manufacturers have developed replacements for lead in many products, until now no commercial replacement existed for lead zirconate titanate (PZT) — the material of choice for transducers, actuators, sensors and microelectromechanical systems used in common electronic devices, the university says."
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Researchers Getting the Lead Out of Electronics

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  • Comment removed (Score:5, Interesting)

    by account_deleted ( 4530225 ) on Wednesday November 19, 2008 @09:04PM (#25827013)
    Comment removed based on user account deletion
    • Re: (Score:3, Informative)

      by mrmeval ( 662166 )

      Water, boron gas, aluminum, etc you tailor it like Chobham armor in layers and with other tricks. You don't really want lead because of the density it doesn't matter much in space unless you're aiming 60 kilotons of it at DC.

      We WILL become more green all this 'waste' is becoming the new gold. Help develop efficient technologies to evacuate landfills of the wealth in them and be the next Bill Grates.

      • Re: (Score:3, Informative)

        by networkBoy ( 774728 )

        I was under the impression that a materials ability to block radiation was (more or less) proportional to it's density. Lead being the densest cheap metal making it ideal. while the mass may not be a problem once in space, it sure is a heck of a penalty in lift weight to get it there though.
        -nB

        • by peragrin ( 659227 ) on Wednesday November 19, 2008 @09:54PM (#25827481)

          So we can't throw 60 tons of lead at DC because the DC politicians are even more dense?

          Sorry offtopic, but we are talking about dense things.

        • by DirtySouthAfrican ( 984664 ) on Wednesday November 19, 2008 @09:57PM (#25827505) Homepage
          It's all about cross section, which roughly depends on the incoming particle's energy being close to the energy of a bound state in the atoms of the material that is to absorb the radiation. The density contributes an overall factor to the calculation. Also, led is nasty when charged particles are involved (electrons, probably protons), because they will rapidly decelerate and create brehmstrahlung, so you've traded a charged particle which is easy to deflect with an X ray, which is not easy to reflect. My wife uses plexiglass shields in her lab for this reason, because it gracefully absorbs beta radiation.
          • so plexi laminate lead then?
            stipulating that we are in space and thus need to protect against *everything* while maintaining a reasonable lift weight, I could see the plexi handling alpha, and beta, but what about gamma and x-rays?
            -nB

            BTW: had no idea about plexi shielding beta... how thick is required?

            • It is probably cheapper to correct the defects caused by uncharged radiation that it is to shield it.

              But, anyway, I'm do not deal with radiation shielding on a daily basis, so that is only a guess.

              • Re: (Score:3, Informative)

                Absolutely, it is. You can use a higher voltage and a process with larger feature sizes to make your electronics more resistent to a bit flip. The larger feature size and voltage means it takes more energy to flip a particular transistor, at the cost of larger circuits and more power consumed.

                You have to add in some buffers to handle the sudden power spikes from particles, so your transistors themselves are safe from damage. Sure, you could still have radiation error events, but they're much less probabl

        • by BluBrick ( 1924 ) <blubrick&gmail,com> on Wednesday November 19, 2008 @10:22PM (#25827721) Homepage

          Actually, extra mass is a problem even once it is in space. Manoeuvring all that extra mass requires greater amounts of energy, which is often somewhat in short supply.

        • by evanbd ( 210358 )

          It depends on the type of radiation you're shielding against. For lower energy but penetrating stuff -- x-rays and gamma rays -- it really only matters how much mass you have. Lead is nice because it makes the shielding thinner, but it doesn't change the weight. In space, you care about mass far more than volume (normally).

          For other sorts of radiation (high energy cosmic rays in particular), lead can actually be very bad shielding. Cosmic rays mostly pass through, but if they hit a nucleus then you get

        • More or less proportional to it's electronic configuration to be precise. More states ~= better. But that scales nicely with mass. ish. Molecules complicate things.

        • Yes, particle radiation shielding is more or less proportional to density. That means that some mass of any material shields more or less the same way. Now, in space you want the more shielding, with less mass (even if it is a very small difference), density is not something that enters in that equation.

          • by hurfy ( 735314 )

            "density is not something that enters in that equation."

            Not entirely true is it?
            If you are building a spaceship around 2 feet of foam instead of around 1" of lead or something it would be bigger requiring more material for outside skin adding mass and size without gaining more shielding.

        • by Lumpy ( 12016 )

          not completely you can easily make it into a foil that is very effective and still light. It's delicate as hell when you get it to the tinfoil thicknesses but sandwiched between two layers of aluminum foil it works incredibly well as a Xray and radiation shield. Far better than 10 thicknesses of Aluminum.

          Just a tidbit from my College life experiences.. The lab professor was really pissy we were generating that high of Xray levels without shielding.

    • Re: (Score:3, Interesting)

      New metal -- wait, what? I think you meant new alloy. And no, this new material shouldn't be any good for shielding; If anything, it would degrade more quickly in a radiation-rich environment than any of its base metals because of the oxygen. But I am not a chemist -- I'm just taking an educated guess here.

    • You send them to space.... and if they do crash you make sure to crash it outside of California so that you don't get the eco-Nazis on your case.
    • by Cyberax ( 705495 ) on Wednesday November 19, 2008 @09:55PM (#25827489)

      Lead is NOT a good shield against cosmic rays. Fast charged particles cause a strong bremsstrahlung (braking radiation) in lead. That's also how X-Rays machines work - fast electrons are slammed into targets made of lead or tungsten.

      High-density polyethylene, water or paraffin work much better for cosmic rays shielding.

      Now, lead is great against gamma-rays. But they are not the principal danger of cosmic rays.

      • Now correct me if I am wrong but back in my chemistry days I'm sure we used a copper target in the x-ray machine. Has a switch been made to lead targets then. I also remember that the single crystal machine (I did mostly powder diffraction work) used a block of lead on the far side to catch the non-scattered radiation. It was a mightly thick block of lead though so I imagine bremsstrahlung radiation wasn't much of a problem.

        • Re: (Score:3, Informative)

          by Cyberax ( 705495 )

          You can use pretty much any heavy metal as a target.

          Copper is used because it has good thermal conductivity and high melting point - only about 1% of energy is converted into x-rays, most of it is dissipated as heat.

      • Since every ounce counts when getting something into orbit I don't see lead being a realistic choice in the first place.

  • Toxicity? (Score:5, Insightful)

    by saleenS281 ( 859657 ) on Wednesday November 19, 2008 @09:07PM (#25827059) Homepage
    So... have they actually tested this on humans to verify it's non-toxic? That's great that we're not using lead, but if this is just as bad for humans when it hits our water supply, what exactly is the benefit? Swapping one (cheap) poison for another (expensive) one?
    • Re:Toxicity? (Score:5, Informative)

      by fuzzyfuzzyfungus ( 1223518 ) on Wednesday November 19, 2008 @09:15PM (#25827125) Journal
      Toxicology can be full of (un)pleasant surprises; but the list of elements involved is promising. Bismuth is a widely accepted nontoxic substitute for lead in applications where similar mechanical properties are needed, and is a component of certain medicines. Iron is generally unproblematic. I'm not sure about Samarium, though our wikipedia overlords say "low to moderate toxicity". Since one of its isotopes has internal medical applications, there are probably some toxicological data out there.

      We'll need to test the compound itself, to be sure; but it probably beats lead.
      • Isn't bismuth also used in pepto bismol?

        • Re:Toxicity? (Score:5, Interesting)

          by worthawholebean ( 1204708 ) on Wednesday November 19, 2008 @10:24PM (#25827735)
          Pepto-Bismol is Bismuth salicylate if I remember correctly.
          • by Toonol ( 1057698 )
            Pepto-Bismol is Bismuth salicylate if I remember correctly.

            I have to interrupt to say this exactly illustrates what a slashdot comment should be. It's like a glimpse of a platonic ideal.
          • by Lumpy ( 12016 )

            Problem is that the element it's self is not the problem it's what it can make when it reacts with others.

            Flouride is mostly harmless and gives us a nice defense to the teeth, but when combined with Hydrogen and Silicon you get H2SiF6 which will eat through you, and the floor, and the glass it's contained in. Incredibly nasty stuff.

        • by Andy Dodd ( 701 )

          Yup, as the other poster said, bismuth salicylate. Kind of implied by your parent post in "is a component of certain medicines".

      • Re:Toxicity? (Score:4, Insightful)

        by hoytak ( 1148181 ) on Wednesday November 19, 2008 @11:42PM (#25828299) Homepage
        Inferring a compound's behavior from the individual elements is error-prone. Carbon is great and nitrogen is great, but CN, well, not so much. On the other hand, this is more true with organic compounds (containing carbon).
        • by ppanon ( 16583 )
          Yeah, cyclic aromatics also have a fairly high tendency to be unhealthy.
        • Re:Toxicity? (Score:4, Informative)

          by fuzzyfuzzyfungus ( 1223518 ) on Thursday November 20, 2008 @01:00AM (#25828789) Journal
          Certainly true, particularly with clever organic stuff. On the plus side, it can at least give you an idea of whether the compound can be rendered safe by incineration, decay, or being metabolized by the right organisms. Particularly with the interest in incineration or plasma pyrolysis for waste disposal, I'd consider a toxic compound made of harmless elements to be a win over a toxic compound made of toxic elements(and, in some circumstances, even a harmless compound made of toxic elements). In the end, we'll just have to feed a bunch of this stuff to bunnies and fuzzy puppies, I suppose.
      • by sdpuppy ( 898535 )

        I'm not sure about Samarium

        If you ingest Samarium, your TV gets all staticy and then your phone rings and someone on the other end says "7 days!"

        ..and then before you die, you see The Ring.

        Need a car analogy to go with that? :-)

      • Re: (Score:3, Insightful)

        by Tubal-Cain ( 1289912 ) *

        Bismuth is a widely accepted nontoxic substitute for lead...

        So? Clorine and Sodium are two very toxic supstances, but NaCl isn't. See also: Thinkgeek [thinkgeek.com]
        Properties of compounds often bear very little relation to their constituent parts.

    • Re:Toxicity? (Score:4, Insightful)

      by sillybilly ( 668960 ) on Wednesday November 19, 2008 @10:16PM (#25827669)
      As long as the product performs somewhere near as well as the old stuff, and it's patentable, then there is money to be made. We just have to find sufficient fault with the old stuff, and bad mouth it enough to start making money. Wikipedia says that as with the other lanthanides, samarium compounds are of low to moderate toxicity, although their toxicity has not been investigated in detail. An MSDS sheet where you can put toxicity N/A, no data available sounds better than one where you know it's toxic, because at least with an unknown there is a chance that it's not toxic. There is money to be made with the patent, and money saved by not having regulations to deal with. Regulations regulate know toxic materials, not unknowns.
  • ...bismuth is radioactive!

  • by Krishnoid ( 984597 ) * on Wednesday November 19, 2008 @09:09PM (#25827083) Journal
    I haven't picked up a soldering iron in a while, but I've heard that non-lead solder has a lot more structural problems than lead solder. Will this stuff have related problems?
    • by Majik Sheff ( 930627 ) on Wednesday November 19, 2008 @09:24PM (#25827209) Journal

      As a technician, RoHS is the bane of my existence. It doesn't flow right, it doesn't wet right, and it doesn't cool right.

      Because RoHS solder is not a true eutectic alloy it tends to separate when thermal conditions aren't precisely right. As a consequence, many manufacturers had huge runs of products that stayed soldered just long enough to get out the door and frequently out of warranty.

      I hope someone comes up with a better substitute soon because I am sick and tired of cracked solder, cracked solder, and cracked solder.

      • Also as a tech, I simply re-solder any failed component with lead/tin.
        RoHS be damned. Though I do work in a prototype environment so meh on the production side.
        -nB

      • by Endo13 ( 1000782 )

        Perfect example being the RROD.

      • Yep. I just had to rework by hand more boards than I'd like to think about. The increased temperature required to reflow the solder already had the contract manufacturer's over maxed out for the panel size I was using - with 63/37 Sn/Pb solder it would never have been a problem - and then a stencil problem caused a bunch of bridges. It would have been a simple matter to fix with lead-based solder, but no matter how much flux you slather on it, it still doesn't flow right.

        So yes, there are RoHS-compliant

      • by Anonymous Coward on Wednesday November 19, 2008 @11:34PM (#25828231)

        You've got to love an environmental measure that ensures a significantly higher failure rate in electronic devices, meaning more electronics to trash -- electronics containing materials much more hazardous than lead. Sheer genius.

        People in first world countries have so little to worry about in terms of health issues that they strain to find bogeymen, and lead has become one of the things filling that role.

        I had one couple fly up from Texas just to see my house in Seattle, make an offer on it, and later rescind the offer because the house was old enough that it existed when lead paint was sometimes used. There was no specific reason to believe the paint was lead-based, and much of the house was wall-papered. The mom was terrified of the possibility of lead and her email withdrawing the offer was filled with heartbreak because they really adored the place; they ended up getting a recent townhome in a much less desirable location. One twist: they knew from the beginning that the attic had loose-fill vermiculite that had a decent chance of containing asbestos, and they had no problems with that.

      • Re: (Score:3, Informative)

        by servognome ( 738846 )

        As a technician, RoHS is the bane of my existence. It doesn't flow right, it doesn't wet right, and it doesn't cool right.
        Because RoHS solder is not a true eutectic alloy it tends to separate when thermal conditions aren't precisely right. As a consequence, many manufacturers had huge runs of products that stayed soldered just long enough to get out the door and frequently out of warranty.

        The problem is many companies think you just change the alloy to lead free, turn the ovens on a little hotter and every

    • by servognome ( 738846 ) on Thursday November 20, 2008 @02:10AM (#25829275)

      I haven't picked up a soldering iron in a while, but I've heard that non-lead solder has a lot more structural problems than lead solder. Will this stuff have related problems?

      As an engineer working on lead-free solder development for electronics, the problems that can arise are specific to the application. The industry has developed a number of different alloys that perform under specific conditions. Instead of just choosing a tin-lead solder that works pretty much everywhere, developers need to understand the types of reliability stresses their product will see and choose the best alloy to meet those requirements. For example lead-free solders that work well in a thermal cycling environment tend to not perform as well under shock conditions. From an assembly side of things, a lot of the problems arise from using old SnPb equipment and materials for soldering joints using leadfree solders. Different reflow temperatures, wetting characteristics, and oxides, means that you just can't use the same old eutectic flux and soldering iron and expect the same quality of results.

      Lead-free solders aren't necessarily problematic, they just require a little more understanding to properly use.

      • by Andy Dodd ( 701 )

        "For example lead-free solders that work well in a thermal cycling environment tend to not perform as well under shock conditions."

        What happens when you have both extensive thermal cycling AND vibration?

      • by Lumpy ( 12016 )

        which makes automotive applications a PITA. Thermal cycling AND shock conditions. I find all the current solders to suck compared to my old standby. Even silver solder outperforms most of the new stuff in automotive uses.

    • by Andy Dodd ( 701 )

      The article title is very misleading. The title claims that a good replacement for lead has been found, but then the summary says it is a replacement compound for one specific lead compound.

      It doesn't seem to address the issue of lead-free solder, which would have been great for my company. We produce mission-critical components that have to endure very harsh environments - as others have said, not a good place for RoHS parts. As "classic" lead-containing parts get harder to find it would be nice if some

  • Reality check... (Score:5, Interesting)

    by girlintraining ( 1395911 ) on Wednesday November 19, 2008 @09:20PM (#25827167)

    Lead: Found in damn near every kind of mining ore. Very common.
    Bismuth: 2x more abundant than gold. Not considered economical to mine for it; Usually had as a byproduct.

    So sure, if you want your production costs to go up up and away, killing your competitive edge, use the eco-friendly BiFeO3. Everyone else, keep pushing recycling and consumer awareness. -_- Oh -- and the icing on the cake? Guess who produces most of the world's bismuth? China, the country best known for producing lead-laden products of much doom.

    • by svnt ( 697929 )

      Lead: Found in damn near every kind of mining ore. Very common.

      The difference is that if my toddler becomes developmentally disabled from licking ore, there is no manufacturer to sue.

      Well, I could try, but I've heard he's got a Hell of a legal team.

      • by girlintraining ( 1395911 ) on Wednesday November 19, 2008 @09:29PM (#25827253)

        If your toddler is licking mining ore I think your first court date will be with child protection services, not the manufacturer.

        • Not to mention that as long as you keep it out of piping and digestive tracts, your levels aren't going to go up enough to matter.

          Lead's also so easy to recycle people do it in their own garages.

      • As opposed to licking circuit boards, which are probably live?

        The problem with lead in electronics wasnt due to immediate risks, the problem was when the products got thrown out.

    • Oh -- and the icing on the cake? Guess who produces most of the world's bismuth? China, the country best known for producing lead-laden products of much doom.

      And why does China produce the most Bismuth?

      Because China produces the most lead from ore (the US refines more lead, but it's largely from scrap, not from ore)... I think China refines about 3x more lead from ore than the US.

      On the plus side, bismuth production facilities are opening in Canada and other countries, on account of increased demand for b

    • What about Samarium? That can't be exactly cheap. I always wonder about the economic viability of electronics that require rare earth metals like some of the high efficiency solar cells designs that have come out.

  • Way Too Late (Score:3, Informative)

    by svnt ( 697929 ) on Wednesday November 19, 2008 @09:22PM (#25827185)

    They may pick up some stragglers that are totally dependent on PZT, but in European consumer electronics, components containing significant PZT have been practically useless since 2006. Europe is not what I would call a small market - as a result, components everywhere are designed to meet the same requirements, meaning these components have suffered from declining demand and/or been removed from company plans.

    "Products that use the new compound could hit the market in about five years, according to the university, after large-scale testing takes place, industry awareness and demand happens, and a method for mass production is created."

    Given that RoHS [wikipedia.org] has already had a staggering impact on the electronics industry, I don't see "maybe 2013, if people figure out that they want this material, and if we can actually mass-produce it" as too reassuring. I'm sure not designing anything in the hopes that a PZT replacement will hit the market sometime next decade.

    Maybe if you're in ultrasonics this is big news?

  • by kimvette ( 919543 ) on Wednesday November 19, 2008 @09:24PM (#25827203) Homepage Journal

    While it's good that they're getting lead out of toys, etc. what about computers, televisions, and other devices/appliances which are generally not regarded as disposable? Is this new solder going to be more reliable than tin, which is notorious for whisker and dendrite formation, which wreaks havoc with reliability?

    Given that you're on /. I'd assume that you know what tin whiskers and dendrites are, but in case you're not here is a refresher:

    http://www.siliconfareast.com/whiskers.htm [siliconfareast.com]

    You can see where this is a problem. And, although it's been discovered that matte tin surfaces and good quality control can reduce the likelihood of whisker formation, what about repairs and installation/reinstallation of components on a mainboard? Replacing integral components (capacitors, sockets, etc.) require high heat, which is sufficient to change the crystalline structure and introduce new stress points for whiskers to "grow," and flexing of the main board from installation of peripherals, connecting devices to sockets, and simple heat/cold cycling will be enough to introduce stress points even in properly-formed, properly-plated components, creating points where whisker formation is more likely.

    Yes, protect the environment, but since more and more electronics are being recycled rather than being dumped in landfills, isn't lead in electronics a non-issue anyhow? I mean, in most localities you're not supposed to chuck monitors and devices containing printed circuit boards in the trash.

    • by Eskarel ( 565631 )
      This isn't for soldering, they've already found a replacement(albeit not a very good one) for lead based solder.

      This is about certain kinds of electrical components which needed to be made out of PZT.

  • $130 / 100g (Score:4, Funny)

    by epine ( 68316 ) on Wednesday November 19, 2008 @09:53PM (#25827477)

    A quick search came up with one site listing the cost of Samarium as $130 per 100g. I'm sure that's cost effective for medical imaging equipment. And I had never realized this, but our local landfill is positively brimming with discarded medical scanning equipment. I might try to scavenge some of this, but all the discarded MRI machines are clumped together by some unseen force.

  • My local radio-station gets the Led out all of the time!
  • Misleading title... (Score:3, Informative)

    by jamiek ( 1242998 ) on Wednesday November 19, 2008 @10:30PM (#25827771)
    FTFA, The researchers have found a replacement for Lead zirconate titanate not LEAD. PZT is a piezoelectric material that contains lead and is used to make actuators and transducers in microelectronics industry. The article itself is pretty poor describing piezoelectric materials as a "switch", so perhaps it is not the fault of the readers for thinking this was a replacement for lead based solders.
  • Why? (Score:5, Insightful)

    by Detritus ( 11846 ) on Wednesday November 19, 2008 @10:40PM (#25827841) Homepage
    I've never seen a justification for the huge amount of money that's been spent on removing lead from electronics. Yes, the stuff can be toxic if ingested in sufficient quantities. No, it isn't going to leap out of your old TV set and perform unnatural acts on your dog. Tin-lead solder has been used for many decades. It's cheap and it works. I can understand why lead was removed from paint and gasoline. It was creating real problems when used in those products. Why, other than catering to the irrational and unfounded fears of the public, are we removing it from electronics?
    • Re:Why? (Score:4, Interesting)

      by BlueStrat ( 756137 ) on Wednesday November 19, 2008 @11:51PM (#25828357)

      Why, other than catering to the irrational and unfounded fears of the public, are we removing it from electronics?

      Isn't that pretty much a politicians' job description these days?

      The environmental lobbies have already pushed through enough regulations to put many U.S. industries out of business and left consumers with no choice but to purchase much more shoddy products manufactured with far less environmental controls from foreign sources. But, I guess that's okay. It's over there, right? It's not like pollution in a foreign country affects us.

      Oh, wait..

      Vacuum tubes come to mind as a good example. I currently design, build, and service vacuum tube musical instrument amplifiers. The tubes being made in China, Russia, and other countries in eastern Europe are crappy-sounding, unreliable, and vary wildly in specs from production-run to production-run, and even within a single run. It's so bad that old-production tubes that have sat in some dusty warehouse for 2 or 3 decades or more sell for unbelievably-high prices.

      USD$400 for a pair of RCA 6L6's!?!? That's *if* you can find them somewhere?

      http://www.kcanostubes.com/products/106/NOS-RCA-6L6GC-Blackplate-Matched-Pairs.htm [kcanostubes.com]

      That's just nuts! The *whole amplifier* these things came in didn't cost that much new at the time!

      I'm also going to keep on using regular 60/40 rosin-core solder in my builds and repairs until and unless they develop a true replacement that doesn't have the 'tin whisker' and other problems associated with current RoHS-compliant solders. If they outlaw it, I guess I'll be an outlaw.

      I can see a future jailhouse conversation:

      "What did they get ya for man?"

      "Possession and distribution."

      "Meth? Crack? Heroin?"

      "Nah, 60/40 solder."

      "Stay away from me, man!"

      Cheers!

      Strat

      • sorry dude, you are dead wrong there, i tell you that as a fellow guitarist.
        because ussr has used tube electronics for much longer than the first world countries, the actual soviet tubes were of a much better quality and newer ones were of a much more modern design (smaller but with the same performance).

        what you mean is that modern russian copies of western tubes suck, but it is a whole different story.

        if you can find some genuine soviet tubes, try to design an amp with them.
        for example try 6n1p or 6n2p fo

        • sorry dude, you are dead wrong there, i tell you that as a fellow guitarist.
          because ussr has used tube electronics for much longer than the first world countries, the actual soviet tubes were of a much better quality and newer ones were of a much more modern design (smaller but with the same performance).

          what you mean is that modern russian copies of western tubes suck, but it is a whole different story.

          if you can find some genuine soviet tubes, try to design an amp with them.
          for example try 6n1p or 6n2p fo

      • Vacuum tubes come to mind as a good example. I currently design, build, and service vacuum tube musical instrument amplifiers. The tubes being made in China, Russia, and other countries in eastern Europe are crappy-sounding, unreliable, and vary wildly in specs from production-run to production-run, and even within a single run

        Really? Because I've found the Eastern European ones to be pretty good. In particular, the Svetlana 6146Bs don't need any particular matching - any two pulled out of the box will b

        • Vacuum tubes come to mind as a good example. I currently design, build, and service vacuum tube musical instrument amplifiers. The tubes being made in China, Russia, and other countries in eastern Europe are crappy-sounding, unreliable, and vary wildly in specs from production-run to production-run, and even within a single run

          Really? Because I've found the Eastern European ones to be pretty good. In particular, the Svetlana 6146Bs don't need any particular matching - any two pulled out of the box will be a

    • it pollutes the environment

      and frankly, i think we need a replacement for lead shot too. that doesn't go away either when you shoot it into the woods. of course, its used because its heavy. i don't know, bismuth shot?

      go ahead, lecture me on relative harm and ppm. i just don't want lead in my environs. am i being irrational? well, the question is: is the 0.000001% increase in bad health effects worth the trade off? in my mind, rednecks with shotguns running around the woods is not worth anything to me to be

  • by dtmos ( 447842 ) on Wednesday November 19, 2008 @10:52PM (#25827935)

    The researchers haven't come up with "a material to replace lead." They've come up with a material to replace lead zirconate titanate, a.k.a. PZT, a piezoelectric and ferroelectric material with many uses in electronics. Because it has an extremely large piezoelectric constant (meaning that it produces a large voltage under little mechanical stress) and is cheap to produce, it is the ceramic frequently used in transducers, sensors, and resonators. The thing on your motherboard that beeps on boot is very likely made of PZT.

    PZT is not, repeat not, used in solder. Wikipedia [wikipedia.org] is one of your many friends.

    Finding a ceramic with similar properties, but without the lead, has been a difficult problem for materials scientists, and the UM researchers say they have finally come up with a viable candidate.

  • how did the bismuth samarium ferrite get to the university's A. James Clark School of Engineering?

  • I've noticed a great deal of my computer components, such as Intel motherboards, as of the last couple years have been listing that they're "RoHS" compliant and "Lead Free." If that's the case, what have they been using?
  • What is this, 2008?
    You know, I might be a little too harsh here.
    Who knows, maybe this was not obvious to these guys.
    Or maybe it was, but took a really long time to test it all out.
    But, as someone who is familiar with Bird Hunting, I can tell you that banning of lead in Bird Shot (shotgun shells) began right about the time the first Apple Computer (no, not the Apple ][ ) arrived.
    The US banned it for bird hunting in 1991. Today, it's more-or-less banned everywhere on Earth where they make any attempt at all t

  • Duh..... (Score:4, Funny)

    by IHC Navistar ( 967161 ) on Thursday November 20, 2008 @02:52AM (#25829471)

    ".....could keep lead out of landfills and the ecosystem, they say."

    -Because everybody knows lead isn't from the environment.

    • by smoker2 ( 750216 )

      ".....could keep lead out of landfills and the ecosystem, they say."

      -Because everybody knows lead isn't from the environment.

      Yeah like coal and oil aren't from the environment either, oh wait, they are found deep underground below the water we drink, and definitely not in the air we we breathe. But now we are into the area of the ecosystem, you know, the area where we all live. If dumping lead into a landfill caused it to return to it's natural state (ore) then it would be fine, but that doesn't happen d

  • In 10, 20, 30 years, or more, someone will discover that this stuff is really bad for us, too. There will be news specials on families who saw high incidence of cancer, birth defects, or who knows what. They'll vouch that it causes autism and Mad Cow Disease. They'll even suggest that we should not be putting tons of this crap into our landfills.

    All new technology looks marvelous today. Hey, once upon a time lead solder was a miracle material for the canning industry! Time brings hindsight, and that's w
  • Wait a Minute (Score:3, Insightful)

    by Nom du Keyboard ( 633989 ) on Thursday November 20, 2008 @11:31AM (#25832509)

    ...could keep lead out of landfills and the ecosystem.

    Wait moment. Isn't lead already in the ecosystem? Don't we dig it out of the ground because it's already there in the ground?

  • PZT is an extremely stable compound, and is not a significant environmental risk. It's an oxide, and it doesn't hydrate, so it's about like any other mineral in the ground. Structurally, the lead is locked up in a cage of TiO6 and ZrO6 polyhedra. It doesn't melt until >2000 degrees F. The lead in it isn't going anywhere.

    Lead in paint? Bad - kids eat it.
    Leas in solder? Bad - leaches in acidic soil.
    Lead in PZT? Fine - it will stay there forever.
  • by Nicopa ( 87617 )

    I misread this as "Researchers getting laid..."

For God's sake, stop researching for a while and begin to think!

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