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Other MidNite Electronics => Other Electronics FAQ'S => Topic started by: Westbranch on March 27, 2015, 05:24:27 PM

Title: Tin Whisker Effect
Post by: Westbranch on March 27, 2015, 05:24:27 PM
How has this issue, Tin Whiskers, affected the production of the Classic and other MN products?

It seems to explain the anecdotal evidence that a lot of consumer electronics products have about a 6 - 10 Year life, used or otherwise...

http://www.aviationtoday.com/av/commercial/System-Design-Death-by-Tin-Whiskers_76599.html#.VRXJoo6lfuc
Title: Re: Tin Whisker Effect
Post by: Mtn Don on March 27, 2015, 08:06:37 PM
 That's a very interesting article. 
Title: Re: Tin Whisker Effect
Post by: TomW on March 28, 2015, 06:02:04 AM
And, again, politics trumps sensibility.

Sorry. Had to say it.  ;D
Title: Re: Tin Whisker Effect
Post by: RossW on March 28, 2015, 06:17:26 AM
Quote from: TomW on March 28, 2015, 06:02:04 AM
And, again, politics trumps sensibility.

Sorry. Had to say it.  ;D

I understood lead-free exemptions were available for medical and avionics applications (amongst others).
Has that changed? (But you're dead right, Tom - nobody seems to factor in "sensibility" in most of these BS decisions!)
Title: Re: Tin Whisker Effect
Post by: mike90045 on March 28, 2015, 10:40:42 AM
Quote from: Mtn Don on March 27, 2015, 08:06:37 PM
That's a very interesting article. 

It's freaking scarey.  Root cause of car accidents and such.    I'd thought the auto mfgs had taken the lead spacing and annealing precautions into account when designing, but apparently not.
Title: Re: Tin Whisker Effect
Post by: vtmaps on March 29, 2015, 08:23:11 AM
A little bit off topic... this subject reminds me of 'dendritic mossing' in batteries (where lead 'whiskers' develop between the plates and short out a battery cell).  I have read that brief (as in pulses) very high loads on a battery can 'burn' up these whiskers and prolong the life of a shorted battery (assuming the short is caused by mossing). 

Back on topic... I wonder if there might be some way to vaporize the tin whiskers with high current pulses...

--vtMaps
Title: Re: Tin Whisker Effect
Post by: mike90045 on March 29, 2015, 01:34:00 PM
Quote from: vtmaps on March 29, 2015, 08:23:11 AM
.....

Back on topic... I wonder if there might be some way to vaporize the tin whiskers with high current pulses...
--vtMaps 

Sure, but the op amp input that was shorted by the whisker will be fried.  it's even a problem in Data Centers with raised floors, the framework is zinc plated to prevent rust (cold air conditioned air)  and hairlike whiskers form, get blown around by airflow, and lodge in power supplies or random places on circuit boards.
http://ecmweb.com/power-quality-archive/how-do-zinc-whiskers-affect-todays-data-centers
But at least, it's repairable on earth, and it's not in space.
Title: Re: Tin Whisker Effect
Post by: Westbranch on March 29, 2015, 02:41:02 PM
More from the same doc Mike posted

See page 25,26,27 of that doc, can't seem to get it copied right now...
Title: Re: Tin Whisker Effect
Post by: Westbranch on March 29, 2015, 03:13:29 PM
and MORE....  page 36

Drywall Sulfur Fumes Blamed for A.C. & Electrical Equipment failures

Pollutants: Not Always in Industrial Settings
• Chinese Drywall Cited in Building Woes
â€" The drywall is emitting sulfur-based gases that are corroding air
conditioner coils, computer wiring and metal picture frames.
• Drywall blamed for A.C. failures
â€" Air-conditioning coils have turned black, along with wiring, piping
and even silver jewelry.
â€" "We have definitely identified that a combination of sulfide gases
are the cause of the corrosion," said Robert P. DeMott, managing
principal of Environ.
â€" "Foul odors reported by people living in the homes may also be
caused by the combination of sulfur gases being released from the
drywall,
• Chinese drywall class action lawsuit
â€" LEE COUNTY, Fla. - The Lawsuit was filed against Knauf Plasterboard
Tianjin Co., LTD, The Knauf Group, Rothchilt International Limited
and the Banner Supply Company.
â€" Known as "Chinese Drywall", it was manufactured oversees and
was made from waste materials. As a result, it emits sulfur
compounds that corrode copper wiring and other metals found in
homes. Copper Corroded by Sulfur flumes
Title: Re: Tin Whisker Effect
Post by: TimBandTech on October 06, 2018, 08:12:36 AM
I was going to say that because they conformal coat their boards that there is no issue with tin whisker effect, but then I bumped into this:

https://nepp.nasa.gov/whisker/reference/tech_papers/kadesch2001-article-dangers-of-tin-whiskers-and-conformal-coat-study.pdf

Here is to dendritic moss. I installed a desulfator on a brand new bank of RS-2ks33ps batteries (48 volts worth) but I have no idea if it is enough for them.

Quote from: vtmaps on March 29, 2015, 08:23:11 AM
A little bit off topic... this subject reminds me of 'dendritic mossing' in batteries (where lead 'whiskers' develop between the plates and short out a battery cell).  I have read that brief (as in pulses) very high loads on a battery can 'burn' up these whiskers and prolong the life of a shorted battery (assuming the short is caused by mossing). 

Back on topic... I wonder if there might be some way to vaporize the tin whiskers with high current pulses...

--vtMaps
Title: Re: Tin Whisker Effect
Post by: boB on October 06, 2018, 02:22:36 PM

Fortunately we don't have much problem with tin whiskers because we still use good old leaded solder.

So far anyway.