New "Liquid Magnet" Solder Could Be Lead-Free Alternative For Electronics


Photo via oskay via Flickr CC

Innovations that help us get the lead out of electronics is a really big deal. The heavy metal is a big source of pollution in soil and ground water tables due to electronics being tossed in landfills, and is a toxic substance in e-waste dumps. University of Maryland is working on what could be the first commercial replacement for the lead used in transducers, actuators, sensors and other components. Researchers at UC Berkeley have been experimenting with bismuth ferrite as a lead replacement in piezoelectric charging in devices. And now Yale researchers have come up with a new soldering material that could eliminate lead in this area of electronics as well, using magnets, rather than heat, to bond materials.

Because lead has a high strength and a low melting point, it's a preferred metal for soldering in electronics because it can be melted onto components without damaging them. Non-lead alternatives have so far been weaker or require more heat to melt, which of course means electronics manufacturers aren't willing to eliminate lead in this area. At least not yet. Cleantechnica reports that a new "liquid magnet" material from Yale could be a solution for getting lead out of soldering in electronics, and it has a revolutionary way of melding with materials:

"The Yale team has come up with a tin-silver alloy that holds micro-particles of iron. Rather than applying heat from an external source, the compound is exposed to a magnetic field. That excites the iron particles, which causes the solder to heat up and melt internally. The result is a highly localized melt that has little or no effect on the components around it. Bourzac explains that the magnetic field also forces the iron particles to line up. The particles hold position when the solder cools, which results in a much stronger bond than possible with conventional non-lead soldering compounds."

Not only does this process mean a strong, low-heat way of soldering electronic components without the toxic lead, it also means increased energy efficiency in manufacturing. The new soldering method could mean easier and cheaper ways to make chips with more computing power, all without the use of lead.

As stated in a Yale University article , "We took this as an opportunity to improve solder for the environment, but we also took it as an opportunity to reexamine how to enhance solder in general," said Ainissa Ramirez, associate professor at the Yale School of Engineering & Applied Science and lead author of the study. "There is a whole range of possibilities for this new kind of solder. In addition to helping make the fabrication of microelectronics more environmentally responsible, these new solders have the potential to solve technological challenges."

This could be a huge boon for electronics manufacturers, as they actively looks to reduce or eliminate the toxic materials currently used in gadgets and appliances.

You can check out a video of the material being used.

More on Lead in Electronics
Getting The Awful, Yet Practically Essential Lead Out of Gadgets
Ditching Lead: Breakthrough Material Helps Us Minimize Lead in Electronics
Toxic Travelling: Lead's Vicious Circle

Tags: Concepts & Prototypes | Gadgets | Pollution

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