Tin Whiskers will cause digital products to fail within 10 years?

[Frank Petronio]

Well I rediscovered Ken Rockwell after years of not reading him, and his mention of the tin whisker problem sounds pretty legit.

With all the engineers here, tell me if this is true or just semi-true? It means my fanciest digital photo toys might well be kaputt around 2022?

Here's some related links and a pull from Kenny boy....

http://www.huffingtonpost.com/2012/0...n_1221076.html

http://www.guardian.co.uk/technology...ch.engineering

From http://www.kenrockwell.com/tech/2012-07.htm:

Tin whiskers are what mysteriously grow out of electronic parts that don't have enough lead in them to stop the problem. When these grow, they start shorting out circuits and causing all sorts of intermittent and permanent weird problems.

Solder is the soft white metal that holds all the parts together on circuit boards. Military and space electronics require at least 3% lead in their solder for precisely this reason. Normal solder is 40% lead, but optional RoHS proposals (that's the little "10" in circles on Nikon lenses and other products) demand no lead.

Consumer products makers love the RoHS/no lead standards, because these whiskers ensure that consumer electronics made without lead will all die in about ten years, so no one will get away with using old products, and have to keep buying new ones.

10 years is a perfect target life: it's long enough that no one blames the makers for deliberately building this in, and long enough that the maker has no warranty or good will problems. "Hey, it was ten years old, what do you expect?" Hey, I have plenty of thirty-year old and older audio and video products working here just perfectly, thank you.

If we all have to replace everything after 10 years, that's a lot of TVs sold. I have a two Visio TVs, a crappy brand, that died on me at 1 year and four years.

Reading the NASA paper, it may be a lot less than 10 years. All AF lenses work with electronics; they have been loaded with circuit boards and microprocessors and memory since the 1980s. Lose a circuit, and even a lens becomes useless.

No one ever died when their lens died, but the news media, sponsored by car ads, certainly doesn't want anyone learning what caused the Toyota unintended acceleration (UA) problems. Toyotas, like most modern cars, are drive-by-wire. Your gas pedal is nothing more than an input to a computer. Cars haven't had gas pedals connected to throttle valves since the 1980s. Toyotas use a variable resistor to encode gas pedal position, and feed that to the computer that does some math, and then controls the fuel injection and air induction systems itself for optimum efficiency.

The unintended accelerations were caused when a tin whisker in the throttle pedal encoder shorted it to make it seem as if the pedal was pushed all the way down!

What do you think, Docs?

[vinny]

We're fuct.

[jp]

More like tinfoil hats rather than tin whiskers. The whiskers are real and do cause problems, but it's highly overrated. This is speculation assuming your electronics will be 24x7 for the next ten years, which is either unlikely, or if your life revolves around it that much, you have backups to prevent data loss due to a failed electronic device. Lenses and AV products don't get that amount of use needed to grow the whiskers, which happen only under specific environmental conditions for energized electronics over a very long period of time. I've had a small datacenter in operation for 11 years now, and don't think anything has failed due to tin whiskers. Blown caps and cheap junk are responsible for most failures.

[Bill_4606]

I agree with the "tin hat" comment. The issue is not with the no lead materials but with the manufacturing quality systems that produce the various assemblies, sub assemblies, and components. Compounding the problem is that about the same technology timeline as no-lead came along the no-clean process reared its ugly head. I can go into the details but you can find much better descriptions than I can provide via the Internet. Anyway, contaminates left by manufacturing process issues are often the real problems... Not the technology. By the way, Do a search on ... dendritic growth ... You'll find some photos of the problem...
Bottom line: if the manufacturing process gets it right, the no lead technology will outlast all of us... But believe me, the manufacturing process is no walk in the park.

[Jody_S]

I have repaired hundreds of electronic devices over the last 30 years, everything from modern Canon lenses to primitive Z80-based microcomputers, 70s stereos, tube radios from the 30s and 40s... I've never seen a 'tin whisker', but I've replaced plenty of crap capacitors.

[Tim Povlick]

I am an EE for the day job although I do not deal with the manufacturing side. I had heard about this back in the late 70's and if memory serves it was silver plating at the time that would cause the whiskers. Two papers to read if anyone wants it straight from the experts (NASA and Tyco Electronics):

http://www.te.com/customersupport/pr...t_whiskers.pdf

http://nepp.nasa.gov/whisker/background/index.htm

A quick skim of these my take away is the problem happens with tin plated items. A PWB passing through the heat flow for soldering will re-flow the tin making it less susceptible to the whiskers forming. It appears to be a problem but not as much as it's being made out to be.

_ .. --
Tim

[Leigh]

Tin whiskers are a well-known phenomenon that has existed for over a century.

It's caused by the formation of filaments of oxides of active metals used in plating of electrical components.

Most electrical contacts were gold-plated until recently, and gold does not form whiskers. Other metals (tin, zinc, cadmium, et al) do form whiskers.

Lead (used as a major component in electrical solder) is effective in reducing or eliminating whisker formation.

Unfortunately, the European RoHS directive in 2006 prohibited the use of lead in consumer products (including the solder used to make them).
Lead is still used in solder for military and space equipment due to its ability to suppress whiskers.

As to "seeing" a tin whisker...
They're usually quite tiny, in the micro-meter range, so not likely to be seen with the naked eye.
I have seen them on volume controls in radios made in the 1930's. In those cases they were larger and easily visible to the naked eye.

Here's a good article from the Guardian (a highly-respected British newspaper): http://www.guardian.co.uk/technology...ch.engineering

Here's the Wikipedia page: http://en.wikipedia.org/wiki/Whisker_(metallurgy)

Google gets over 200,000 hits for "tin whiskers" RoHS.

- Leigh

[RichardSperry]

I've had a small datacenter in operation for 11 years now, and don't think anything has failed due to tin whiskers. Blown caps and cheap junk are responsible for most failures.

Perhaps the blown caps and cheap junk failed because of tin whiskers?

[Leigh]

I've had a small datacenter in operation for 11 years now, and don't think anything has failed due to tin whiskers.

The RoHS directive only took effect six years ago.
Most equipment sold even after that date used tin/lead solder, I wouldn't expect you to see problems yet.

Wait another ten years.

- Leigh

[jnantz]

there will probably be an implant by then, nano technology made asteroid mined algae
kind of like a brother from another planet kind of thing but better.
who cares about crappy electronics made in china from now ...

its like " archival pigment prints " turning magenta in just a few years ...
or light jet prints lasting 75 years but color-shifting in just a few months ...

things from now aren't meant to last more than a few years,
except for the orgazmatron or the orb, or the 67' beetle in a cave...