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Tin Whiskers are
microscopic single-crystal metal fibers, thinner than a human hair, capable
of bridging great distances between leads on electronic components, and
creating short-circuits and failures. They are almost invisible to the
eye, needing magnification and special lighting to be seen.
They are real.
People in the general public arena are beginning to talk about them. Here
is a recent Slashdot post:
Tin whiskers - fact or fiction? 2008-06-13 10:09 bLanark Submitted
by bLanark on Friday June 13, @10:09AM
Some time ago, most electronics were soldered with old-fashioned lead
solder, which has been tried and tested for decades. In 2006, the EU banned
lead in solder, and so most manufacturers switched to a lead-free solder.
Most made the switch in advance, I guess due to shelf-life of products
and ironing out problems working with the new material.
Lead is added to solder as it melts at low temperature, but also, it
prevents the solder from growing "whiskers" — crystalline limbs
of metal.
The affect of whiskers on soldered equipment would include random short-circuits
and strange RF-effects. Whiskers can grow fairly quickly and become quite
long
Robert Cringley wrote up this some time ago, and, it seems that the world
has *not* been taking notice. I guess cars (probably around 30 processors
in a modern car) and almost every appliance would be liable to fail sooner
than expected due to tin whiskers. Note that accelerated life-expectancy
tests can't simulate the passing of time for whiskers to grow.
I've googled and there is plenty of research into
the effects of tin whiskers. I should point out that the wikipedia page
linked to above states that tin whisker problems "are negligible
in modern alloys", but can we trust Wikipedia?
So, my question is: was the tin whisker problem overhyped, was it an
initial problem that has been solved in the few years since lead-free
solder came into use, or is it affecting anyone already?
To answer the last question, let us just say that Wikipedia material
can be posted by anyone and can be edited by anyone.
What it means to the average consumer is that your brand new wide-screen
television set will likely fail in only a few years, due to tin whiskers
growing from one lead to another on the integrated circuits inside it.
Most have only a one-year warranty.
The consumer buys a wide range of products containing electronics, ranging
from cars to cellphones to coffee-makers to computers.
The pure-tin-plated electronics are inside not only consumer products
but industrial products such as computers which are the workhorse of modern
business, and routers that are the backbone of the Internet, modern data
storage and retrieval systems, telecommunicatons systems, nuclear- and
conventional-power-plant control systems, automobiles, just about anything
with electronics in it. All are at risk, and all can (and do) fail from
this cause.
There is a clear and present danger to our society from the advent of
pure-tin-plated electronic components and the attendant Tin Whiskers.
The NASA website http://nepp.nasa.gov/whisker/
gives scientific facts about the history of failures (except those that
manufacturers don’t want to be made public), satellite failures and their
costs, what we know and what we don't, about what causes them and what
cures them.
Here's the bottom line: We do not fully understand what causes them. Not
even by half. Worse, we cannot cure them.
They are a disaster-in-the-making. They have destroyed billions of dollars
worth of satellites. They have created "incidents" at nuclear
power plants, including a false shut-down command at the Millstone nuclear
reactor in Millstone, Connecticut about two years ago. What if that false
logic signal had been a command to "Slam Full On!" instead of
"Slam Full Off!"? Would we have had a meltdown such as Three
Mile Island, or even Chernobyl? I hope not, but no one knows.
Then, there's the implanted pacemakers, diagnostic and life-support medical
equipment. The medical electronics community is VERY concerned about this.
The jokes about recalling implanted pacemakers aren't funny.
We (American and foreign components manufacturers, many with offices in
U. S. jurisdiction) created them by plating our electronic component leads
with pure tin. Having done that, there is no known cure for the resulting
tin whiskers and the electronic failures they create. THERE IS NO CURE
to prevent tin whiskers from growing, unless you get rid of the pure tin.
Even if someone claimed to have invented a metal alloy or surface-treatment
that would magically stop them, how do you prove it? These things take
many months to many years, even ten years or more, to grow and do their
damage.....and then the communications satellite dies, one of the computers
controlling your automobile operations fails and perhaps the brakes jam
on at high-speed on a freeway.....who knows what happens when there's
a random computer malfunction? How do you prove there’s not one chance
in a thousand of something not happening in ten years, or even three?
How many years does it take to “prove “ that, while our infrastructure
and the products of our civilization crumble around us at a faster and
faster rate?
It takes forever to prove that something won't happen.
The cure is not to continue to experiment and do research, year after
year. There will NEVER be enough time to prove that tin whiskers will
not grow out of some specially-treated version of tin.
This civilization made a tremendous blunder, and now we know the consequences
of that blunder. Something happened: Tin Whiskers.
Remember the "Blue-Screen-Of-Death" when the early versions
of Windows failed and you lost all your computer work? Tin Whiskers represent
an Early Warning for our civilization and the electronics infrastructure
on which it depends for road traffic lights, air traffic flight control
and more. If we do not deal effectively with this now, the future is Blue.
There is a conformal-coating under development, that promises to "contain"
them, meaning to buckle them before they can puncture it, escape, creating
a short-circuit and the attendant failure of the product, be it a satellite
or your cell-phone. That's not here today, and it might not be in your
consumer products in the future, because it adds costs to the manufactured
product and the manufacturer will sell you the lowest-quality product
that you will just barely tolerate and likely come back for more. That's
not just an opinion, it's the conclusion of a study by Sandia, a U. S.
Government National Laboratory, from an assessment of the quality level
that military contractors had to specify from their suppliers in order
to get what they needed so things would work. That was over fifty years
ago, and some things don't change.
How did we get into this mess?
Over fifty years ago, scientists at Bell Laboratories knew about this,
and studied how to make solder and how to electroplate leads of electronic
components so things could be assembled, and be reliable.
What did they find? A metal mixture (alloy) of tin and lead was simple,
inexpensive and highly reliable. The tin-lead solder joints were tough,
a bit flexible (not brittle), thus able to withstand mechanical shock,
so electronic assemblies could be built and put in rockets, airplanes,
cars and even your watch (and if you dropped that watch, it could "take
a licking and keep on ticking"). This tin-lead alloy called “solder”
had been in wide use before that, and continued to be used to join electronic
components and circuitry.
So, everything was fine. Scientists know how to make things work; they
tell the manufacturers; correctly made products are produced; we all get
on with our lives. Where did our civilization go off-the-rails?
If governments passed a law that said the Earth was flat, it would be
the Law, and the Earth would be flat. Accidents would happen, but no one
would understand why. Is the law wrong?
If a law was passed that said the Sun revolved around the earth, that's
what everyone would believe...because they were told to. Of course, certain
astronomers might have problems explaining the physical reality of what
they observed, because there was a law that said the Sun revolved around
the Earth, and Punishment awaited anyone who disagreed.
Do you know that only a few hundred years ago, within the sphere of influence
of the Pope, that's the way it was?
Science cannot be legislated.
If you try to legislate Science, there will be consequences. It's not
nice to fool Mother Nature.
And yet, that's exactly what happened when the European Union (EU) created
a decree called RoHS, or the Restriction of Hazardous Substances directive.
In a nutshell, it decreed that lead was awful and it would be banned.
No one had ever gotten lead poisoning by eating electronic components
with lead in the solder, and no one had ever gotten lead poisoning from
lead that might have been in the water leached out of a dump where electronics
junk might have been discarded...there was no known reason to do it except
that people could be made afraid, by pointing to lead that was poisonous
if you ate it, and pointing to lead in the solder alloy, and saying that
they were the same. “Anything is identical to any other thing.”
There was NO independent scientific investigation or evaluation of RoHS
consequences or Environmental Impact Asessment, as has been a law in the
U. S. since 1969, first for the Federal government and now for all State
and City governments.
The worldwide scientific community did not wake up to what was happening
until things were many years down the road. By then, component manufacturers
in the U. S. and around the world had made the business decision to climb
on the bandwagon instead of fighting the European Union, and the entire
electronics manufacturing infrastructure of the world was in a headlong
rush to change from tin-lead-alloy-plated electronic components to pure-tin-plated,
and most of it already has. Why? Because everyone else was doing it.
U. S. manufacturers thought they had to obey a EU directive, regardless
of its scientific foundation or lack thereof. They did so because they
wanted to continue to market their products in Europe.
Have you ever heard the expression, "Sow the wind, and reap the whirlwind?"
Here we are: Thirty-plus-billion-dollars (and climbing) of cost to society,
fantastic amounts of wasted productivity, hundreds of thousands of engineers
trying to design things that work when civilization does a very foolish
thing and tries to make things that fail sooner, components that fail
sooner, and where is the benefit? If you accidentally eat your cellphone,
you won't die of lead poisoning.
Just because millions of people do a foolish thing, does not mean that
it is not a foolish thing.
With lead no longer "allowed" in solder or in the plating of
the component leads, new solders had to be developed. The replacement
solders are strange alloys of tin, silver and copper, and sometimes bismuth.
They have their own problems. Bismuth is actually radioactive, did you
know that? Apparently it's not hazardous.
That's the mess we are in. How do we get out?
THERE IS NO SUBSTITUTE FOR LEAD IN SOLDER. That's just a scientific fact.
An alloy of even a few percent lead in the tin is enough to stop tin whiskers
from growing. More, about thirty to sixty percent, and we have reasonably
shock-resistant solder that provides mechanical connections of parts to
circuit boards, and has none of the whisker-problems or brittle-fracture
problems we now have.
This was known around the world, half-a-century ago. What do we do today?
Go back to doing what worked, and stop doing what does not.
Question the Authority that tells us to do something scientifically stupid.
Scientific observation of reality tells us how things work. Passing laws
that say otherwise is stupid and destructive.
Is that controversial? You, the reader of this, have a mind of your own.
I invite you to use it and look for yourself and see what is a foolish
thing to do, and what is an intelligent thing to do.
Read the data on the NASA website. It contains facts. It documents failures.
It shows causes.
I offer the following suggestion as an intelligent thing to do: Go back
to using lead in solder, and solder-plated leads on electronic components.
Many of the aerospace / military / high reliability manufacturers never
left the use of lead. They are creating new manufacturing practices and
technologies to eliminate the pure tin plating and/or new coatings to
prevent the tin whiskers from causing short circuits. All of this costs
money (your tax dollars at work), but is absolutely necessary given the
alternatives.
If we continue down the path of RoHS, the destructive results will continue,
and will grow, doing greater harm to the environment and creating more
than the tens, even a hundred billion dollars of wasted energy and wasted
productivity and vastly more attendant environmental pollution than that
already caused.
Many are already headed in the wrong direction. How do a few concerned
citizens stop this before it is too late?
The continuing manufacture and importation of electronics equipment and
components as “lead-free” into the United States of America in the absence
of an Environmental Impact Assessment (EIA), done on a scientifically
sound basis, would seem to be a violation of The National Environmental
Policy Act of 1969 and subsequent legislation.
That law is here: www.nepa.gov/
Ask the United States Government and your State Government, via your elected
Federal and State representatives, to produce the Environmental Impact
Assessment for Pure-Tin-Plated Electronic Components, and if one does
not exist to do an Environmental Impact Assessment on Pure-Tin-Plated
Electronic Components.
Further information may be found at the NASA website http://nepp.nasa.gov/whisker/.
Please click on the element below to visit and read, The Case for Lead.
Copyright
© 2009-2021 Steve Smith all rights reserved
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