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Zinc Whiskers Cripple Colorado's Computers

Mr. Christmas Lights writes "While zinc whiskers, small metallic fibers which grow on surfaces that have been electroplated with zinc, aren't a problem for Christmas lights, they can cause serious problems for computers. The Denver Post reports how they caused computer outages for the last three weeks in the Colorado secretary of state's office. This basically halted business and elections document filings. Zinc whiskers are becoming more of a problem as computers electronics get smaller. NASA has a good reference site which includes a interesting PDF summary paper complete with pictures. /.'ers with computer rooms might want to check this out."

5 of 276 comments (clear)

  1. I RTFA and it's not the computers, it's the floor! by the_rajah · · Score: 5, Informative

    The metal frames for the raised floor are where the zinc whiskers are coming from. They get sucked into the power supplies and short them out.

    "Do the Right Thing. It will gratify some people and astound the rest." - Mark Twain

    --


    "Do the Right Thing. It will gratify some people and astound the rest." - Mark Twain
  2. Hospital ORs have problems with Zinc whiskers by Anonymous Coward · · Score: 5, Informative

    I work in a large midwest hospital, and we've got a constant issue with Zinc whiskers in our network jacks in operating rooms. Supposedly the origin is the cleaning solutions that they use for the floor.

  3. And Sea-Water too. by OceanWave · · Score: 5, Informative

    I know I speak against my own name, here. But:

    Living by the sea, especially with the high humidity that comes with it...and the salt...can give your more than just a few zinc whiskers on the PC board.

    Salt oxidation--depending on how long the windows are open--can really eat a PC in two years or less; never mind the quality of the MB.

    Sea salt is hydrophilic. If it accumulates on something, episodes of high humidity will attract moisture from the air, and add the basis for typical corrosive effects. I have had containers with dry sea salt, which have pulled moisture out of the air on their own.

    (Most acids need water...so does salt to release it's own ions, which can have a corrsive effect similar to an acid on metallic equipment...usually involving the non-metal in the salt. Sea salt has lots of chlorine, a very strong oxidizing agent.)

  4. Re:What about conformal coating? by Animats · · Score: 5, Informative
    I wish. Automotive electronic units are routinely conformal coated, but most consumer devices are not. Many blank boards have a masked insulating layer on top, but that's different than a conformal coat. A conformal coat is applied after the parts are mounted, so the whole board becomes a sealed unit.

    You can conformal-coat boards yourself, using Fine-L-Kote spray. We use this stuff on the Overbot.

    It's a flammable, toxic chemical mixture until it dries; you need gloves, goggles, a respirator mask, and proper flammable liquid storage. Cover connectors with masking tape before spraying. It's a clear coat, but glows in UV, so you can check for missed spots.

  5. Re:Absolutely no way by shostiru · · Score: 5, Informative
    You simply cannot convince me that this is a real problem that we need to worry about.

    and therein lies the problem: you just asserted that this is an item of faith for you, not reason; facts be damned, you cannot be convinced.

    Never mind that there are several companies who do raised subfloors who've been addressing this problem for some time. They're all peddling snake oil, and NASA is helping them do it.

    Never mind that Zn whiskers grow slowly, Zn-electroplated subfloor panels in data centers aren't that old, and PC board density has been increasing. Or that they only occur on electroplated zinc, and only grow long enough to be problematic in very low traffic areas. Nope, must be bogus.

    Never mind that hospitals are affected as well and take this seriously. Or that the condition is well known among electroplaters and materials engineers, and was discussed at least ten years ago in the literature. Or that it's been involved in at least one product liability case. Or that Bell Labs has known about it for over fifty years (since 1948).

    And never mind you could have found everything I mentioned above within the first 30 google results for "Zinc Whiskers". Nope. It must all be a myth, because there's no such thing as newly discovered age-related problems.

    (Oh, and I hear that automobile corrosion is a myth too ... I went to the new car lot and looked around and didn't see any, so it must not exist)