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Researchers Getting the Lead Out of Electronics
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."
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
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.
The Christian Right is Neither (Christian nor right). See: Matthew 23, Matthew 25, Ezekiel 16:48-50
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.
Women are like electronics: you don't know how damaged they are until you try to turn them on.
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.
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.
Ahh - My eye!
The doctor said I'm not supposed to get Slashdot in it!
Hey, no fair actually knowing how physics work! Here we are, all sci-FI about things, and you barge in with just sci... you must think you're sooooooo much better than the rest of us don't you?
Good day sir, I say good day.
Try not to take me more seriously than I take myself.
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.