Most companies do not necessarily want to change to lead-free production, but are motivated by a combination of factors. The WEEE/RoHS directives in Europe have instilled fear of legislation that will prohibit the use of lead in electronics soldering. Any country disallowing electronic products with lead or other hazardous substances will create a trade barrier. Marketing of a lead-free program by many companies will lead to fears of being caught behind. Many companies are also worried about cost and reliability factors too.

Operating costs are increasing because some substitute chemicals are more expensive than the hazardous chemicals they replace. Companies also will face higher energy bills, because alternative processes such as using lead-free solder or brominated flame retardants require anywhere from 6 to 18 percent more energy. The cost of educating and training company personnel on the use of lead-free alloys and qualifying lead-free parts are not inexpensive ventures. As the production of lead-free components ramps up to high volumes, at least some of these costs should stabilize or drop, industry spokespersons agree.

In the connector industry, lead is often used in tin-lead alloys as surface finish for solder terminations, or as a protective coating for shell housings and on accessories. The use of lead added to tin has been around for many years as the best low-cost solution for soldering processes - with an average solder temperature of 183°C. The alloy provides better mechanical properties than pure tin or lead. Industry experience shows that the lead added to tin reduces the risk of whisker growth.

Tin whiskers are hair-like growths of near-perfect crystalline structures of tin that grow from some electroplated tin surfaces. The whiskers are believed to grow in response to mechanical stresses acting within the tin layer. Today, the exact process for tin whisker growth is still unknown. Whiskers are a reliability concern for electronics, because they can cause shorts and other problems. At present, no official and safe test concerning whisker formation is available for review in the highly debated use of pure tin.

Close up of Tin Whiskers on a Relay	Epoxy Mounted Cap: whiskers on terminations	Close up of Tin Whiskers on Armature	Tin Whiskers growing on a MATTE tin-plated copper leadframe
Photos courtesy of NASA GSFC

Here are additional photo samples of whiskers in Electromagnetic Relays, Ceramic Chip Capacitors, Terminal Rings, Hybrid Microcircuit, Microcircuit (DIP), Test Points and Connectors

Another concern for manufacturers is the labeling requirements for lead-free components. Eco-labels are visible product labels that identify products meeting specific environmental requirements. Recognizing the importance of environmental communications and the corresponding potential for inaccurate and misleading environmental claims, the International Standards Organization (ISO) has undertaken efforts to provide standards and guidance for environmental claims. For detailed information on labeling programs, visit http://leadfree.ipc.org/.