Pentagon Seeks Secret of Seashells, Antlers

CLEVELAND — The Pentagon is trying to find out what makes reindeer antlers and seashells so tough but light. The answer could mean better protection for soldiers and pilots, as well as stronger cars, medical implants and bowling balls.

“We need very lightweight, thin, high-strength materials,” said Wilbur C. Simmons of the Army Research Office near Durham, N.C., which commissioned the $2-million study.

Researchers at three universities are involved in the five-year project. Case Western Reserve University in Cleveland will study antlers, the University of Washington will examine seashells and Princeton University will do both.

Researchers will study the ceramic-type properties that provide a seashell’s hardness and the organic properties that enable antlers to absorb such shocks as the collision of two male reindeer charging each other. They will also try to understand why they are light.

“If you’re going to have an application of say, armor, you don’t want to carry all that weight around your body or on a tank or planes,” said Ilhan Aksay, who is directing the research at Princeton.

“In both cases, the idea is to look at structures and learn lessons from the way nature designed them and see if we can design similar structures through synthetics,” he said.

Studying items from nature is “the cutting edge of research in materials,” said Frank N. Kelley, dean of polymer science and engineering at the University of Akron.

At Akron, researchers are trying to determine why a spider web is stronger than nylon. The goal is to learn what lends special properties to natural materials. For example, why do trees bend but not break?

At Case Western Reserve, researchers hope to duplicate the toughness and fast-growing property of antlers through “biomimickry”--the manufacture of a synthetic material based on a principle found in nature.

Antlers interest scientists because the velvet-covered horns are incredibly sturdy and grow yearly, said Eric Baer, director of the research at Case Western Reserve. At their peak, antlers can grow an inch a day.

Antlers are stronger than bone, possibly because of complex layers of protein and minerals, scientists think.

Their makeup may give clues to creating materials that could lead to sturdier medical implants, bowling balls that never nick and automobile panels that resist chips and dings from gravel.

And the Pentagon is interested in anything that offers better protection against bullets and shrapnel.

Baer has been promised a free supply of antlers from the herd of five Greenland reindeer at the Cleveland Metroparks Zoo. Reindeer, both bucks and does, shed antlers yearly.

Alan Sironen, reindeer keeper at the zoo, said he has gained respect for both the strength of reindeer and the toughness of their antlers. He has seen reindeer lift 15-foot, 10-inch-diameter tree trunks and push aside huge piles of brush with their antlers.

Baer said he hopes to develop materials that are less prone to drying out than antlers. As they dry, the antlers become brittle.

Baer said mass production of antler-tough material must also be faster than the six months it took to grow the 16-point antler that sits in his office.

“We’re not interested in synthesizing an antler in the laboratory,” he said.