What are Zinc Whiskers and How Can You Prevent Them?
- Consider using raised floor tiles that don’t rely on zinc coating.
- Consider products that offer a hot-dip galvanized zinc coating – the hot-dip includes an extra layer of coating that puts the zinc under much less pressure than that of electroplating.
How do you mitigate tin whiskers?
The best strategy to prevent tin whisker induced failure of electronic hardware is to avoid using pure tin plating on any of the parts used in the construction of the electronic hardware, such as lead finishes, RF shields, mounting hardware, and electronic enclosures.
How do zinc whiskers affect today’s data centers?
Although the whiskers are small in size, they are large enough to cause problems in today’s microcircuits such as short circuits, voltage variances, and other signal disturbances. When sensitive electronic equipment becomes contaminated with zinc whiskers, equipment failures and system resets can occur.
What are zinc whiskers?
Zinc whiskers are crystals that form on the surfaces of steel items that have been electroplated with zinc. They can form on any zinc electroplated metal surface. For data centers, this can mean the plenum sides of raised floor tiles, pedestals, stringers, cable and runway trays and other infrastructural supports.
What causes tin whiskers to grow?
The exact cause of tin whisker growth is still not fully understood. It is known that a whisker grows from its base and that the tin around the base does not thin as the whisker grows. It seems that the energy for growth comes from microstrains present in the tin or from externally applied pressure.
What is tin mitigation?
An integrated, quantitative, standardized methodology is proposed whereby mitigation levels can be selected that are appropriate for specific applications of pure tin for given end-uses. A popular choice for material finishes is tin except for the steel finish on mechanical parts where a common finish choice is zinc.
Are tin whiskers still a problem?
An Overview of the Problem Tin whiskers are real. They are microscopic conductive fibers emanating from pure tin surfaces, and they pose a serious problem to electronics of all types. Tin whiskers are not a new phenomenon resulting from the switch to lead-free electronics.
Why are tin whiskers bad?
Tin whiskers are metal filaments which grow from tin. Because of their current carrying ability and low electrical resistance, whiskers are a threat to electronic circuits. The ability of tin whiskers to cause electronic circuit problems was established in 1951.
What causes tin whisker growth?
What is meant by tin whiskers?
Tin whiskers (also called Sn whiskers or metal whiskers) are microscopic, conductive, hair-like crystals that emanate spontaneously from pure tin (especially electroplated tin) surfaces. Whiskers form primarily on elemental metals, but have also been found on alloys.
What causes tin whiskering?
What causes metal whiskers?
Metal whiskering is a phenomenon which occurs in electrical devices when metals form long whisker-like projections over time. It was noticed that small metal hairs or tendrils grew between metal solder pads causing short circuits. Metal whiskers form in the presence of compressive stress.
Are zinc whiskers a health hazard?
Raise Your Awareness. • Zinc Whiskers Have Caused Extensive Failures to Electronic Systems. – Potential “Health” Hazard from Breathing Zinc Whisker Debris is Unknown. However, there is a general understanding that needle-shaped particulate material can present a special hazard to lungs regardless of material.
Do zinc whiskers cause electrical shorts?
Zinc whiskers are conductive and therefore they will cause electrical shortsif they manage to bridge tightly-spaced electrical conductors. Now that zinc whisker-induced shorts have been so convincingly demonstrated, some former “seemingly inexplicable” shorts are now regarded as explainable as having been caused by zinc whiskers.
When were tin whiskers first reported?
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. Other examples of metals that may form whiskers include some tin alloys, zinc, cadmium, indium, antimony, silver among others .
What are tin whiskers and how do they affect electrical systems?
Numerous electronic system failures have been attributed to short circuits caused by tin whiskers that bridge closely-spaced circuit elements maintained at different electrical potentials. Tin whiskers are not a new phenomenon. Indeed, the first published reports of tin whiskers date back to the 1940s and 1950s.
