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"What Are Tin Whiskers?"
Tin whiskers are not a new phenomenon. Indeed, the first published reports of tin whiskers date back to the 1940s and 1950s. Tin is only one of several metals that is known to be capable of growing whiskers.
Definition of Metal Whiskers
Thin hair-like growths on metal that are barely visible to the naked eye, they are stronger than the metals from which they are formed, probably because they are free from defects.
From Metalinfo.com via About.com
SOFT-METAL WHISKERS
Tiny metallic protrusions that grow like hair from soft metals, are a problem that can cause electronic short circuits leading, in some cases, to the failure of heart pacemakers, avionic relays, and satellites. What to do with the unwanted whiskers---and, in the first place, understanding how they form---is a problem that's been around for fifty years.
What are the Mechanisms by which Tin Whiskers Form?
The mechanisms by which tin whiskers grow have been studied for many years. A single accepted explanation of the mechanisms has NOT been established. Some theories suggest that tin whiskers may grow in response to a mechanism of stress relief (especially "compressive" stress) within the tin plating. Other theories contend that growth may be attributable to recrystallization and abnormal grain growth processes affecting the tin grain structure (which may or may not be affected by residual stress in the tin plated film).
Zinc Whiskers Wreak Havoc On Computer Systems
You've probably never heard of "zinc whiskers" but a quick Google search will result in hundreds of website hits describing the phenomenon and the costly consequences to computer data centers which have raised access flooring. If your company has experienced unexplained hardware failures or data corruption problems, zinc whiskers could be the culprit.
Zinc whiskers are extremely small filaments of zinc that can grow over long periods of time on metal surfaces that have been electroplated with zinc for corrosion protection. These types of surfaces may be found on the underside of zinc plated raised access flooring, zinc-plated floor supports/rails and computer equipment racks, and even mechanical hardware (such as nuts, bolts and washers) used in hi-tech environments. If disturbed by maintenance, construction or moving of equipment, these electrically conductive structures can become airborne and if deposited on exposed circuits may cause intermittent to permanent electrical shorts and system failures concurrently or sometimes within weeks of the activity.
Also: http://nepp.nasa.gov/whisker/
Metal Whiskers
Metal whiskers are a crystalline metallurgical phenomenon whereby metal grows tiny, filiform hairs. The effect is primarily seen on elemental metals but also occurs with alloys.
What are Tin Whiskers?
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