Mitigation techniques for tin whiskers

This article is the first of a two part series on the problem of tin whiskers facing design engineers in the fields of medical equipment, defense, and aerospace. Many industries are currently switching materials levels used in electrical and electronic equipment to meet various government required levels of hazardous substances. For example, lead is being phased out in favor of tin alloy solder and finishes. The medical equipment, defense, and aerospace industries are currently exempt from these regulations and they generally use leaded parts which are not as prone to developing tin whiskers that can cause a component to fail. The concern is that as more demand rises for compliant parts, part-suppliers will produce only compliant parts and the leaded products will become more expensive and harder to obtain. Design engineers will probably be forced to switch to tin alloy solders eventually which raises questions about material strength after the switch. There is still much unknown about tin whiskers and how to prevent them from occurring. While this is not a serious concern in home appliances, it is critical for aircraft manufactures where the stresses are high and the required lifespan is long.   Read the full article in Design News.

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