Sandia LabNews

There's gold (plating) in them thar hills (of Livermore)!


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Often, it’s the things behind the scenes that are crucial, like the airbags hidden beneath the dashboard in your car or the hydrogen getter that keeps your waterproof flashlight from exploding. The Center 8700 materials manufacturing labs have been in the business of making hidden — yet essential — devices since Sandia has been in Livermore.

The materials labs boast a full range of capabilities. The plating shop, plastics lab, and composites shop churn out devices of practically any size, shape, material, or function. In addition to manufacturing, Sandia researchers use the capabilities of the materials labs to look for new solutions to science and engineering problems.

“At Sandia, we always do things a little differently. Sometimes it’s because of classification, sometimes because off-the-shelf products just don’t fit our needs,” says Tim Shepodd (8778). “We need a strong scientific and manufacturing base to make things happen, and the materials manufacturing labs are a key element of this capability.”

Tim is manager of Materials Chemistry Dept. 8778. The department’s plating shop recently had a breakthrough in the development of gold-plated items.

“We’ve hit the gold standard on gold plating,” Tim says. “We’re making devices with emissivity that matches commercial calibration standards.”

Low emissivity requires a fine grain structure. The plating baths for the ultrafine grain-size gold were developed for the LIGA program and now enable plating for heat flow control devices.

While gold plating is common with simple shapes — think of fireplace doors or jewelry — applying gold to Sandia geometries while maintaining uniform low emissivities is a challenge. The breakthrough came in collaboration with Gas Transfer Systems Dept. 8224. In terms of controlling heat-flow, Sandia has taken gold plating to the limits of physics.

The plastics lab at Sandia/California creates a full range of materials in polymer science. The lab’s capabilities in foam production range from energy-absorbing devices to structural materials; some are strong enough for tools, and others for lightweight materials, like a surfboard core. (TufFoam®, developed in the plastics lab by researcher LeRoy Whinnery, has received a great deal of public attention for its applicability to the surfboard “blank” industry.)

Foam, in fact, shows up in a lot of places where you might not expect it. There are foams sandwiched in some armor plating for blast mitigation and shock isolation, for instance. Foam has also proven to be an excellent means of large-scale decontamination of physical structures, as demonstrated in Sandia’s licensed foam technology.

If you own a waterproof flashlight, there’s a good chance it is embedded with a device that originated in the Materials Chemistry department. A Sandia-licensed hydrogen getter, developed by the plastics lab staff, is now used by a major battery manufacturer in millions of flashlights every year. This getter, while small in size, is a crucial safety feature.

Environmental advances in batteries eliminated most of the toxic mercury, making batteries greener, but created a problem of hydrogen buildup, especially in sealed waterproof devices. If enough hydrogen builds up, the gases can explode. The Sandia-invented getter effectively scavenges undesired hydrogen, thus eliminating the hazardous properties of trapped hydrogen.

More than 10 million of these getters have been produced in the last 10 years and are found worldwide in commercial products.

The plastics lab also supports hydrogen getters for the stockpile and provides rigid foam for fixing components within devices. Just as the components of a printed circuit board are fixed together, the internal “guts” of weapons systems are potted to prevent damage to crucial elements.

Another important lab at Sandia/California is the composites lab, which is capable of producing a full range of composites structures. A recent, significant composite is TEPIC, a tooling material that won an R&D 100 award in 2005.

The characteristics of TEPIC — high-temperature stability, low cost, and high strength, to name a few — make it ideal for processing advanced composites. TEPIC solves a common manufacturing difficulty, replacing composite parts when tooling no longer exists or only the old, possibly broken part remains. The casting characteristics of TEPIC permit the fabrication of tooling directly from an existing structure. The dimensional and feature fidelity of the resulting mold is sufficient to permit the use of the mold with minimal additional machining.

The production of composites and foams sounds very messy, but all these labs are designed for minimal environmental impact. The plating shop sits on a big catch pan, which collects all the waste water for recycling. Most discarded paper, metal, and empty reagent containers are also recycled. “The goal is to impact the environment as little as possible,” says Tim.