Zinc Whiskers or zinc needles:Metal coatings can grow in the correct environment, causing expensive damage to computers and clean rooms.
Scratched zinc plated low carbon steel enclosure of an AC power supply is causing zinc whiskers to be found within the product that the AC power supply is located in. Scratch has caused bare metal to be exposed with no signs of corrosion present.'The Phenomenon of Zinc Whisker Growth and the Rotary Switch' by J.R.Downs and R.M.Francis in the Aug. '94 issue of Metal Finishing magazine.
Cadmium Whiskers, cadmium plated parts
Cadmium vaporizes (sublimes) easily on earth at elevated temperatures from its solid state, without melting. Also, it sublimes at lower and lower temperatures as the surrounding pressure decreases. If its vapor pressure is higher than the surrounding pressure, it will sublime.
The legal definition of 'asbestos'
is any inorganic substance that has a 100:1 length-to-width ratio or greater. By this definition, zinc whiskers are classified as asbestos and a manufacturer could be sued on the grounds that the company is exposing their workers to asbestos. This legal definition is different than the true geologic definition of asbestos, which has this description in addition to others but is limited to a small range of silicate minerals. As a side note, 95% of all asbestos does NOT cause lung cancer. They do, however, causes asbestosis, which is the scarring of lung tissue as these crystals get stuck in the lung, which more research needs to be done.Are Zinc whiskers growing in your computer room? PDF Doc
Photos of whiskers:
Medical Equipment Failures
Commercial (non-NASA) Satellite Failures