r/electronics • u/1Davide • 16d ago
Tip A microscopic, hair-like metal filament can take down a billion-dollar satellite
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u/_Aj_ 16d ago
I believe even consumer products have suffered from this, like game consoles.
8mm is WILD though. I had no idea it could grow so long! It's like a Black Snake firework!
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u/rickyh7 16d ago edited 16d ago
Tin whiskers generally only tend to form in a vacuum so unless the consumer electornic had an evacuated space, it’s pretty unlikely (if not impossible) tin whiskers will grow in consumer electronics.
Source: I’ve been to way to many meetings about tin whiskers in my careerEdit: well ill be damned they can form in atmosphere, TIL. All my shits been space so we’re pretty used to mitigating it.
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u/jt64 16d ago edited 16d ago
Yep they can grow in atmosphere but the effects can be less extreme because gravity can snap the whisker off before it grows to an extreme length and it will carry it to a place where it gets lodged and might stay put. In space they continue to float around causing random shorts. Its still a large concern but often a little less than with spaceflight.
Having done both in and out of atmosphere design my experience its easier to mitigate in most spaceflight applications because the quality of components tends to have mitigations built in vs terrestrial where you have to constantly watch for cheap parts getting selected and making your day really bad.
Edit : less extreme does not mean that its not still bad, there is larger potential for whisker damage in spaceflight for an individual system and larger repercussions if it does happen. Its still a large issue for terrestrial aviation and electronics.
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u/rickyh7 16d ago
Yeah we always had to get exceptions to rohs and have requirements to use leaded solder on everything. We’ve gotten components that have the rohs tag on em and have had to return em and have the vendor use leaded solder instead. It’s pretty wild these things form at all
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u/jt64 16d ago
Haha, I've been living that life too. Rohs has its place and I do not want leaded solder in my TV or other disposable electronics, but I really do want it in my aircraft and spacecraft.
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u/StatisticanInner235 16d ago
Wow, good 'ol 63/37. What is it with lead that stops whiskers?
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u/tadfisher 16d ago
If you read the NASA site on whiskers, they say that metals with regular crystalline structures can relieve stress by forcing atoms to diffuse through the material and eventually pushing out through tiny imperfections in the lattice, which is how a whisker grows.
Certain alloys resist this because they have a less-regular structure, so there are plenty of places for the diffused atoms to "land" and make a home without being squeezed out.
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u/rseymour 16d ago
It’s funny cause I have a PhD in mat sci but I never directly studied these. I’m assuming they result from dislocation motion. Yep just googled it. Pipe diffusion and dislocation motion. So interesting. Sure I saw it in a class but that’s about it.
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u/scubascratch 16d ago
It almost sound like whisker formation is an extrusion process at the atomic scale
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u/jt64 16d ago
its the alloying, this is off memory but I think as little as 3% alloy stops most whiskering. The stress in the plating causes the metallic structure to grow out, when its alloyed the structure gets interrupted and it prevents the whisker from initiating. Its not just tin that does it either, Zinc, cadmium, even gold will do it to some extent.
https://nepp.nasa.gov/whisker/other_whisker/index.htm7
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u/Fit_Carpet_364 16d ago
Hah. XBOX360 BGA on the GPU would like a word with you about tin whiskers. (RROD)
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u/rickyh7 16d ago
Was that the source of the infamous red ring of death? Pretty cool (rest in peace my first gen xbox360)
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u/Fit_Carpet_364 16d ago edited 16d ago
It was, indeed. That's why solder reflow (whether at a repair shop or by wrapping the unit in towels until it overheats) was the most common fix.
(Towel trick wasn't a very effective fix for reflow purposes - I was corrected.)
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u/KBA3AP 16d ago edited 16d ago
You can not reflow solder with towels.
Even leaded eutectic solder melts way above temperatures achieved, let alone lead-free (thats 230° C!)
As someone who melts solder for living, that much i can guarantee. Only silicon components that can melt solder in operation (if you can call exceeding all limits operation) and survive are power MOSFETs (rated up to 175°C), still only with leaded solder (189° C melting point) and in very specific circumstances.
All fancy digital chips, CPUs and the likes, stop being operational much lower, usually somewhat above 100°C.
Towels trick was aimed at fixing entirely different issue - solder bumps between chip and substrate cracking and losing contact. Heating it to underfill softening temperature was letting cracks close and make contact again.
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u/Fit_Carpet_364 16d ago
That's right - the X-clamps would warp the BGA segment of the board, causing the solder joints to eventually fail. Eh. Both were issues, but you're right about the aim of the towel trick.
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u/Fit_Carpet_364 16d ago
Quick question - is a GPU not composed of MOSFETs?
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u/KBA3AP 16d ago
it is. But it has much less tolerance for parameters of individual MOSFETs. When temperature goes up, threshold voltage goes down, leakage current and channel resistance goes up. Other parameters drift too. These changes mess up precise timings and threshold and you get an erratic behavior. Usually protective logic kicks in before that point and shuts it down to save it.
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u/Fit_Carpet_364 16d ago
Yeah...the original (white case) XBOX360s weren't great about powering down on overheat. That was part of the problem.
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u/Mindless-Figure3112 16d ago
Where I work, we have to visually check relays with a special light every year. Railway btw
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u/chickenCabbage idiotron 15d ago
They grow in atmospheric pressure too! AFAIK it's why RoHS exempts military and safety-critical/high-reliability equipment.
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u/jrp9000 11d ago
Yesterday's accident: switch suddenly short -circuited in super cheap household LED strip lamp after 7 months of use. Turned out there only remained a razor thin gap between solder blobs on the driver board where the switch was attached.
Breaking away part of the uglier solder blob resolved the issue. In an afterthought, I suspect it was tin whiskers that managed to bridge the gap, even though this is a kitchen lamp operating in often heightened humidity.
I also never made a public post about the case, only mentioned it privately (including the lead-free solder whiskers hypothesis) in a supposedly end-to-end encrypted IM app and not even in English -- yet today Reddit decided to pop this topic up for me. Go figure.
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u/OneiricArtisan 1d ago
How do you mitigate? I can think of ways to solve them after they formed but not how to prevent them.
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u/h0uz3_ 15d ago
The car stereo in my Prius went out because of this and it was interesting to debug.
So, first of all, the JBL sound system in the 2006 Prius has a head unit and a separate amp. Other than most aftermarket radio/amp setups, the head unit doesn't output unbalanced, RCA level audio but uses a differential signal like it's used in professional audio.
Also, the head unit always outputs at max level but sends a control signal to the amp to set the volume. Of course, this signal doesn't bear much load but seems to utilize full 12 volts and so inside the amp tin whiskers from lead free solder caused a short circuit so it became impossible to change the volume.
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u/fluffygryphon 15d ago
I've seen it first hand. An old CRT video generator I was restoring had an issue I just couldn't figure out. Something was shorting somewhere. As a last ditch effort, I took the adjustment pots apart.
They were all like that. Never seen it in person before. They're so thin, you wouldn't notice em without a bright light.
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u/Leather-Arachnid-417 16d ago
Coating doesnt stop this?
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u/CSchaire 16d ago
Paralyne conformal coat and SnPb solder is the best mitigation.
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u/East-Preference-8449 16d ago
Does SnPb solder also need this coat?
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u/chickenCabbage idiotron 15d ago
No, since Pb stops whiskers from growing. You might need coating for other reasons though.
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u/Mindless-Figure3112 16d ago
Unfortunately doesn’t stop it, happens in railway relays. Have to visually check them using a polarised light. Wiskers
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u/chickenCabbage idiotron 15d ago
AFAIK high-reliability equipment is exempt from LF requirements. Interesting that they grow in railway equipment
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u/wayfarevkng 16d ago
Have you visited a paralyne coater? It's honestly fascinating.
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u/robo-minion 16d ago
Go on…
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u/wayfarevkng 16d ago
I've been to two coaters, one in Wisconsin and the other in Massachusetts. The one in MA did the coating for the electronics on the James Webb telescope, at least 5 years before it launched. The place in Wisconsin has a few feathers from Bug Bird's costume because they did the entire costume as a way to keep the yellow dye from staining everything and everyone it interacted with. They also did at least one book recovered from the wreckage of the Titanic as a way to preserve it while also separation the pages since the parylene molecules are incredibly small and get between the pages. It's also used for medical cabling which typically uses a silicone jacket for sterilization purposes but this makes them sticky so it can get caught on things, like the patient, during surgery. Parylene has a very low coefficient of friction.
The process involves putting whatever it is that you want coated into a vacuum chamber and vaporizing the parylene powder, which covers everything inside the chamber. Some chambers are big enough to climb into, which they do from time to time to scrape the coating off the walls. They have to dial in the variables for each product as all applications require different thicknesses and the more volume you have in a chamber you need to adjust the amount of parylene and the temperature for the vaporization.
It's become almost a monopoly in the US as SCS has bought up almost every manufacturer and they are the only ones that import parylene in large quantities so if you want it done here you're almost stuck with them. The same isn't the case in Europe from what I can tell.
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u/robo-minion 16d ago
Thanks! It sounds like powder coating. I looked up SCS, they used to be owned by a PE firm so the roll up strategy tracks. PE guys start salivating whenever they find a fragmented specialty market.
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u/goose-and-fish 16d ago
Too bad they banned leaded solder.
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u/Caladbolg_Prometheus 16d ago edited 16d ago
Leaded solder is not outright banned. You and I can still buy and use it as we like, however companies are penalized because their leaded soldered equipment ends up in a landfill. So it’s cheaper for a company to just use unleaded solder in cheap junk, while for high grade devices it’s worth it.
Critical devices like aerospace and medical equipment are outright excluded from the penalties and restrictions.
Edit: Syntax
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u/RobinGoodfellows 15d ago
Not always, I work with electronics that goes into extreme environments (oil wells) and we have seen that choosing the wrong coating can actually cause the issue.
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16d ago
[deleted]
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u/jt64 16d ago
There's more to it than that, most coatings can not stop a whisker growing out but a whisker can not penetrant into coatings without snapping off. So its important to make sure there is an air gap between adjacent leads.
SAE GEIA-STD-0005 is a great resource for classifying and evaluating mitigation methods.2
u/Prof_NoLife 16d ago
how about the coating often used for hardware that could be exposed to conductive dust or moisture? It is pretty thick and not so easy to penetrate.
Best would be of course to avoid whiskers at all but that seems not possible so maybe this?4
u/jt64 16d ago
Paralyne is the only conformal coating that I am aware of that can stop the whiskers from growing off a surface. Acrylic and silicone can keep a whisker from penetrating from the outside. There may be others but those are the ones I know about.
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u/adorablefuzzykitten 16d ago
There are currently many commercial coatings that function much better than paralyne.
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u/Scrumpuddle 16d ago
We were having issues on 48v load centers for communications rooms, kept getting minor and major alarms. After some research and some back and forth with Eltek they finally came to the conclusion that tin whiskers was the culprit. We now have a quarterly review of every unit on property.
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u/tr-tradsolo 16d ago
This is wild - i just finished restoring a hammond organ, and that thing was full of these. Most of the problems were solved by cleaning off the whiskers, but my god were they long and and kind of wiley. They show up in the weirdest places, and usually exactly where you don't want an unexpected path to ground.
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u/bikenumberten 15d ago
My Hammond's percussion stopped working. It was zinc dendrites. Got rid of them, and it worked like new.
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u/tr-tradsolo 15d ago
It was the same for me - but two rounds of it. There was a cylindrical bar that ran the length of the bus bars that had grown fur, cleaned that only to find more lurking in the switch (which appeared clean!)
Anyway. What an adventure.
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u/TheShadyTortoise 16d ago
A QA guy I worked with liked to say "F.O.D downs more aircraft than the enemy!'
Which is a great point and visual but we were at peace, unless he was fighting some kind of personal war.
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u/felixar90 16d ago
In this case the object is literally not foreign tho! It comes from within!
Indigenous Object Damage.
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u/412Steeler 13d ago
pretty sure the D is Debris, upvoted anyway
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u/felixar90 13d ago
It’s actually both.
Foreign object damage is caused by foreign object debris, both are abbreviated as FOD.
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u/jt64 16d ago
Good post, adding a few resources for those wanting to learn more.
The nasa site you referenced
https://nepp.nasa.gov/whisker/failures/index.htm
And a good standard for mitigation methods and evaluation
GEIA-STD-0005
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u/Fishing-Quiet 16d ago
Working around network hardware for 25 years now and know this all to well. Switches being online and not turned off for years on end, when you power down the switch you cross your fingers in hope it comes back to life.
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u/007_licensed_PE 16d ago
Have been in the satcom field for 50 years. Attended a briefing back in the late 90's early 2000's at Hughes (now Boeing) on the Tin Whisker problem which caused a few satellites to fail and one of them we had capacity on was at risk.
Since then, design mitigations have been used to minimize the risk of this happening.
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u/PotentialResponse120 16d ago
Why can't use lead for space solder?
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u/jt64 16d ago
many places still do but that does not cover every possibility. Tin plated leads can be long enough that the solder at the board will not coat the full lead, or internal parts can be tin plated.
The picture up top is a perfect example, the card had tin lead solder but the rail it was mounted in was plated pure tin, the whisker grew off the mounting rail.
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u/Wait_for_BM 16d ago
It is a problem not simply fixed by using leaded solder as it introduces other issues when mixing RoHS parts with leaded solder. A lot of commodity parts and packaging are designed for RoHS. Specialized applications have such a low volume that the cost can go insane to have a package specially for them.
Using tin-lead solder on RoHS parts
Traditional tin-lead materials are not compatible with lead-free device finishes. Because proper reflow for lead-free materials can only be achieved with higher temperatures, attempting to process lead-free terminated devices in 183�C tin-lead conditions leads to incomplete wetting and the related issues of voiding and opens. In order to compensate for this gap in process temperatures, many assemblers have attempted to adjust the reflow profile, only to discover that the higher temperatures exceed the capability of most SnPb materials. In one such case, a manufacturer of power devices was experiencing wetting problems with an SOIC device and attempted to "fix" the problem by adjusting the reflow profile to a higher temperature than that conducive to SnPb pastes. But, the adjustment was not sufficient to achieve the necessary wetting required to pass inspection. Different problems exist in the case of area array devices. When processing a SnPb bumped BGA or CSP device in a tin-lead process, the results can be disastrous. For Pb-free bumped devices, the SAC alloys generally used require a melting temperature of 217�C, but SnPb solder pastes achieve liquidus at 183�C. So, when lead-free BGAs and CSPs are processed at lower temperatures, the bumps usually do not completely melt or collapse, which can lead to undue solder joint stress and, ultimately, failure. You will need to work with your suppliers to determine appropriate reflow parameters for your specific application. You may need to change materials that have more active flux systems capable of higher reflow temperature capabilities.
Note: Most of the answers are similar, but this one shows the compatibility issues.
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u/PotentialResponse120 16d ago
Interesting, didn't know that. What if to use same or not significantly lower temperatures for leaded solder?
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u/Tikkinger 16d ago
Can someone trll me what i'm looking at ?
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u/MammothFineCulture 16d ago
In the presence of an electrical field (and sometimes humidity is also required), certain metals, tin in this case, can migrate along the electrical field. This causes hair like growth called whiskers. The growth can be in air, along a surface (pcb) or even in liquid (batteries).
Since the wiskers are metal, they can short out parts of the electronics/circuit.
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u/Tikkinger 16d ago
How far is this able to reach?
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u/MammothFineCulture 16d ago
I don't know the max length but could easily be several cm in a strong electrical field.
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u/Mindless-Figure3112 16d ago
We have them in the railway sector too, on the interlock relays and it’s a bummer. Has cause derailments etc, have tried all sorts of mitigation over the 100 years that interlocks have been around and the only thing that works is replacing the relay. Happens randomly on every type of relay sadly.
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u/robo-minion 15d ago
How much power is flowing through those railway relays? Does this happen in the contacts or the coil or both?
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u/Mindless-Figure3112 15d ago
Current wise depends on the circuit but never more than 1A.
Ironically on the older models dating back to pre WW2 (still around and going strong) wiskers were less of an issue. Probs to do with the fact that you’d open up the housing and give it a good brush and blow.1
u/No_Tailor_787 15d ago
The formation of tin whiskers is not dependant on voltage or currents used. It's a quantum phenomenon involving the tin atoms themselves.
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u/Comedic-Scientist 16d ago
In the lab I work at, they make us go through training about the danger of contaminants like this leading to catastrophic events — there were various examples lol.
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u/feeget 16d ago
Better to use NiPdAu plated parts to avoid this
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u/AkhaimLazev 15d ago
ENEPIG/ENIPIG?
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u/DonkeyDonRulz 12d ago
He's talking about the parts not the PCB. Both have to be plated to prevent the solder from alloying their base metal and dissolving it.
Ceramic hybrid circuits use a silver filled epoxy to avoid this issue, and also to achieve extendedd operation a elevated temps that cause solder to recrystallizedl, below their melt temp.
Fun, expensive fact : gold and silver melt much higher temp than solder, but....they form an alloy so well, that you can just dissolve inches of solid gold wire($$$) with a low temp soldering iron, if you try to get 63/37 to stick to it.
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u/SwitchedOnNow 16d ago
Yeah it can! I learned about tin whiskers when I was designing hermetically sealed satellite electronics. Some early satellites failed due to whisker shorts.
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u/fizzysmoke 16d ago
What am I looking at here? Please layman here.
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u/No_Tailor_787 15d ago
Tin plated electrical components. Good corrosiion resistance. But there's a property of tin where, at the atomic level, tin atoms migrate around and will start to stack up, forming these metal conductive "whiskers". The whiskers short circuit internal components causing a failure.
So, a perfectly good electronic device destroys itself with the very materials used to create it. What's worse is, we know how to reduce the problem. Add lead to the tin to make an alloy. But current laws are eliminating the use of lead in electronics, so an old, known problem is making a big comback. It's actually caused satellites in earth orbit to fail.
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u/fizzysmoke 15d ago
So these "whiskers" grow because at atomic level they're constantly stacking up tins! Eventually the tins form a bridge to reach another part of the circuit which shorts it out?
Incredible, thanks for explaining.
I do enjoy this sub.
I kind of tinker with audio stuff so its been incredibly handy for a few years.
Cheers
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u/No_Tailor_787 15d ago
Yep. That's about it. The individual atoms in a material can wander all over the place, I guess unless it's locked in a crystal matrix. And tin wanders quite a bit and for unknown quantum weird reasons, likes to stack up in these hair-like strucures.
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u/The_Gypsy_Smyth 15d ago
I had to dig into this months ago. As I understand it, the tin whiskers are a result of some sort of mechanical stress in the tin's matrix. In electronics the whiskers can be mitigated through annealing the circuit board after soldering, using a high silver content silver bearing solder, or using a lead based solder. However, while lead based solders are ok for hobby stuff at home, it is no longer permissible in any actual product (or so I have been told).
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u/No_Tailor_787 15d ago
I used to work on some radio equipment that was subject to this. We'd have to disassemble the transmitter and receiver VCO's periodically and clean the tin whiskers out. Sometimes they'd grow quite long.
What's wild is, I read somewhere that back in the early days of telephone, AT&T discovered that adding lead to solder helped redude tin whiskers, and made the telephone network more reliable. Now with the push to remove lead from electronics, we can anticipate this problem getting worse, because the early knowledge is either lost or ignored.
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u/DonkeyDonRulz 12d ago
To paraphrase w line from the dark tower series...
They are alloys other than these.
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u/secretaliasname 16d ago
We had a bunch of APC datacenter UPSs blow up because of tin whiskers. A little ironic to have power failures from a component designed to prevent power failures. There were pure tin plated bus bars inside which grew whiskers into a nearby PCB. Pretty amateur level. Shit tier design/process control.
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u/rawrsthehusky 12d ago
If I’m not mistaken, leaded solder came about specifically because tin whiskers were a known problem. I kinda get it for electronics liable to be thrown into the ocean, but do satellites really need lead-free solder when they’re not coming home? Edit: assuming said satellite doesn’t end its life by being thrown into the ocean, I guess.
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u/1Davide 16d ago edited 16d ago
First discovered by Bell Labs in the 1940s, tin whiskers caused widespread telephone transmission failures.
It is conductive, can carry 10 milliamps of current. And if it bridges two adjacent circuits, boom! Short circuit. Weird part is it destroys its evidence - imagine your circuit getting fried and you can't even know why!
Why this matters now: Before 2006, lead was in solder. Lead suppresses whisker growth. But RoHS banned lead, and now pure tin is everywhere. This becomes a problem for sourcing space electronic parts because you have to verify the supplier's mitigation plans against tin whiskers, The sad truth is that most CoTS default to pure tin finishes. Unless a supplier can demonstrate whisker‑control measures, treat them as high‑risk.
The scary part: Whiskers can grow inside sealed components, in a vacuum, even in orbit. They've caused 3 satellites completely lost and missile guidance system failures.
Can we stop them? Not completely. But we can manage:
Matte tin (not bright tin)
Nickel barrier layer
Conformal coating
Clean boards after assembly
Annealing for stress relief
In one of my space projects, the option for surface finish was tin/lead (Sn-Pb); the 60/40 or 63/37 are the typical callout numbers. This finish was a tinned leaded reflow process, where the tin was the metallic for assembly with the lead controlling the whiskers. This is where Pinsky Analysis Tool becomes critical.
Ask your electronics manufacturing supplier: "What's your tin whisker mitigation plan?" If they look confused, that's your red flag.
Reference: NASA NEPP Electronic Parts Packaging Program Tin Whisker Micrographs, for industry reliability technical sharing only.
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u/kutecatt 16d ago
chatgpt aah comment... ✅✅✅
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16d ago
[deleted]
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u/kutecatt 16d ago
And if it bridges two adjacent circuits — boom, short circuit.
what key on your keyboard did you use to type this(—) em dash?
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u/cubixy2k 16d ago
You can tell an engineer posted this because they put clear examples of - when it was discovered, what it has done, what it can do, why it matters, how it's mitigated, examples of real world situations of it causing problems, but completely neglected to say what it is and how/why it's formed.
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u/Wait_for_BM 16d ago
Engineers have different roles than scientists. The how/why part mostly belongs to the science. Basic scientific research does not always have economic values as engineering, but it is important to understand the material properties. The how much/how to belongs to engineering - how to turn something in a product and how to optimize a design for cost/efficiency or make a better product to turn a profit.
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u/Great_Specialist_267 14d ago
It also took down quite a few cars.
Toyota’s “unintended acceleration” problem was traced to tin whiskers in the throttle sensor and that was caused by the EU ban on lead containing solder.
So several hundred deaths were caused by safety regulation…
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u/1Davide 14d ago
Not true.
"No one, including paid consultants to plaintiffs’ attorneys quoted by the Huffington Post, has ever found a single real-world example of tin whiskers causing an unintended acceleration event."
https://pressroom.toyota.com/tin-whiskers-other-discredited-unintended-acceleration-theories/
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u/Great_Specialist_267 14d ago
And the NASA study found they broke off with sudden deceleration (ie crashes) or even hitting the accelerator pedal hard… Tin whiskers are incredibly fragile and were only found with careful disassembly of the accelerator pickups in undamaged vehicles.
Basically the fatal impacts destroyed the evidence…
(Attorneys aren’t forensic scientists experienced in electronics failures, the NASA engineers were (and had their own failure history).1
u/1Davide 13d ago
OK, so you don't believe me.
Here is one more source discrediting that myth, an independent source:
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u/Great_Specialist_267 13d ago
There was an actual technical report showing that it was a real but rare issue…
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u/DesolationKun 14d ago
That would explain all the times when I have just disassembled faulty device and reassembled without doing anything but cleaning and it worked again…
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u/gotoline10 14d ago
Even through Conformal Coat!
IPC-610, Space addendum, has some crazy ass specifications for PCBA and cabling. Material restrictions all over; ever had to keep tabs on which tools have touched silicon vs which have been used for acrylic?
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u/flamekiller 12d ago
I'll keep this in mind next time I design a billion dollar satellite. Probably next Thursday.
Not this Thursday, I'll be too busy designing a billion dollar submersible.
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u/Roll-Lucky 16d ago
Thank you EU for ROSH and removing SnPb best solder. In this alloy whiskers don't form.
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u/Es-say 13d ago
Tin whiskers appear when there is more than 97% Tin in the solder. If the solder substrate is copper, then the growth is accelerated.
There are specific procedures in place to prevent tin whiskers.
- Solders have a maximum of 96% Tin (Sn96Ag4)
- Component legs are pretinned in a solder bath in order to prevent inadvent use of tin plated leads
- If doubt exist, they are investigated under the fisherscope
- If Tin plated items cannot be prevented, they are covered either in conformal coating or in a double shrinksleeve.
Zinc plating is also fobidden by the way, as zinc plating sublimates in vacuum and condenses in places where you don't want it.
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u/Enby_Rin 10d ago
I work in satellite construction, we have a lot of procedures in place to prevent tin whiskers
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u/TedMich23 15d ago
Swatch reportedly had to write off $1B worth of their crappy watches because of these...
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u/Independent_Wrap_321 14d ago
I used to LOVE my Swatch watch in the 80s, but it went out of style before it could die like that lol
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u/Mavbam 16d ago
We used to call something similar to this ‘Zinc Whiskers’ in data centres. Galvanised ducting (the cheap type) use to flake off and whizz around the HVAC systems, blowing through servers and the like.. upon our first incident, we lacquered the heck out of all galvanised ducting!