Tin Whiskering Borders on Urban Legend

Tin Whiskering Borders on Urban Legend

Some in the components industry believe way too much is being made about the risk of tin whiskering in lead-free components. Whiskering can occur in pure tin solder or tin finishes when components are under stress. According to Arnold Offner, Phoenix Contact's industry standards manager and program manager for RoHS and WEEE, tin whiskering has been identified and effectively mitigated by component manufacturers. "We know that tin whiskering is associated with stress either in the manufacturing process or the environment the product works in," says Offner. "And we know it has to do with the plating."

Offner believes the phenomenon has been mitigated by using tin in combination with other metals. "We have a tin finish over a copper alloy on our products, with nickel in between." He notes Phoenix Contact is confident in its solution in part because it uses its own components in its automation manufacturing systems. "We're using our own products, so we can police it," says Offner. He notes that component suppliers have used considerable testing in the development of lead-free parts. "People are creating test criteria that include 6,000 hours of testing," notes Offner. "That puts the kibosh on the risk of tin whiskering."

Sales of Hybrid and Diesel Cars are Rising Sharply

J.D. Power-LMC Automotive Forecasting Services reported that U.S. sales of diesel and gas-electric hybrid vehicles will likely double over the next seven years, reaching nearly 11 percent of the passenger car market. The firm expects hybrid cars-which accounted for half of one percent of domestic car sales in 2004-will rise to a 3.5 percent market share by 2012. Hybrids will constitute 4.8 percent of the U.S. auto market this year. Diesels are expected to grow from a 3 percent market share in 2004 to 7.5 percent in 2012.

The forecasting group said rising gas prices have prompted the rise in sales of "green" vehicles. "Higher gas prices are acting as a catalyst for automakers and consumers to find alternatives to the traditional gasoline internal combustion engine," says Anthony Pratt, senior manager of global powertrain forecasting at the forecasting group. Hybrid vehicles combine a regular gasoline engine with an electric motor and battery in which the act of braking captures lost energy, enabling the car to save fuel and emit fewer pollutants.

Engineers Should Help Their Companies Go Green

While design engineers are normally expected to design for manufacturability, they are now becoming the front line in the transition to environmentally compliant products. Supply chain company, i2 Technologies, has released a paper, "Hazardous Materials Management for the Electronics Industries," that puts much of the responsibility for the move to green products on design engineers. "Engineers must extend their responsibilities beyond 'design for manufacturability' to now include 'design for environment,'" notes the report.