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Jewelery made by materials engineers integrates technology and style

Some may already have noticed an added splash of style around the engineering campus--perhaps a silvery reflection of light from a fine, hand-crafted bolo, or a deep, warm, golden glow emanating from the intriguing geometric patterns of earrings and tie pins. These exquisite renderings come not from traditional purveyors of fine jewelry, but from the engineers in the Department of Materials Science and Engineering.

It all started two years ago as staff began to dismantle the old foundry. In one of the old induction furnaces was found a piece of 99-percent pure aluminum with large grain size.


Chris Kailhofer inspects aluminum pieces that will be made into jewelry. (large image)

"We conducted grain growth experiments. We put samples in an air furnace for varying lengths of time to see how big the grain would get. It turned out best when we left them in overnight," said Chris Kailhofer, an instrumentation technologist in the Department of Materials Science and Engineering. "And then someone looked at it and said 'Hey, this would make nice jewelry.'"

Kailhofer borrowed a punch press from the Department of Mechanical Engineering to punch out round and square aluminum samples. The samples are placed in an air furnace and are then etched in hot sodium hydroxide to remove oxidation. The pieces are then treated with Poulton's Reagent (a mixture of hydrochloric, nitric and hydrofluoric acids) to make the grain stand out.

After etching, the pieces are washed and mounted in an anodizer. (The anodizer was built with the help of staff from high energy physics. Kailhofer swapped an old overhead crane for a spare power supply.)

The anodizer creates a clear and porous surface coating of aluminum oxide on the aluminum. The pieces are colored in a dye bath and finally placed in boiling water, which seals them by changing the structure of the oxide. Attach some hooks and pins from a local jewelry store, and you have "EnginEarrings," tie pins and bolos.

"We made a batch with help from students and sold them during Expo for $3 to $10 a piece. We sold about $1,000 worth," Kailhofer said. "We also gave them away to high school seniors during a Society of Women Engineers summer session."

There are no plans to manufacture the jewelry on a large scale, however those that contribute $25 or more to the Kohler Partnership for Materials Science and Engineering will get the EnginEarring item of their choice free. They are available in gold tone and silver tone and may be available in other colors in the future.

For more information contact Chris Kailhofer,