Heavy hitters

Heavy hitters

UNB researchers are testing the limits of materials to protect against big impacts
March 19, 2013

John Spray is trying to figure out how to better protect soldiers from roadside bombs, astronauts from hurtling space junk and aircraft from becoming crippled by bird strikes. The answers could literally be out of this world.

Director of the Planetary and Space Science Centre at the University of New Brunswick (UNB), Spray is determined to use the geological knowledge he has gained from more than 30 years of studying natural craters to make new armour.

From a warehouse in the woods on the fringes of Fredericton, Spray and a team of engineers are translating their knowledge of planetary science and meteorite impacts to test how different materials can withstand the strain when small objects are fired at them at speeds comparable to those of falling meteorites. “Some of the work we do for the military is classified, for obvious reasons,” says Spray from the floor of the warehouse, which houses two “guns” that use compressed gases to fire projectiles at speeds of up to 28,800 kilometres per hour.

The longest of the guns, stretching 23 metres in length, is funded by the Canada Foundation for Innovation (CFI). It is outfitted with a $600,000 camera, which follows the projectiles and their impacts, capturing multiple images in the blink of an eye. The images show a small, round metal object as it hits the surface of metal, plastic, ceramic or even textile. The team then examines how the material withstands the hit or perhaps even changes composition, with the goal of developing supermaterials.

Running the only facility of its kind in the country comes with its own challenges. Spray, a Canada Research Chair in Planetary Materials in UNB’s department of earth sciences, and his colleagues must invent techniques for their experiments and have even built their own supercomputer. “There is no Firing Light Gas Guns for Dummies,” says Spray. “We’re lucky to have funding so that we can learn our craft.”

His quest has also piqued the interest of the private sector. In 2008, American aerospace giant Lockheed Martin announced a $4 million investment to help open the lab. But Lockheed Martin isn’t the only big corporate client — Canada’s Bombardier has worked with the lab for five years on a variety of projects.

“We expect these opportunities to grow,” says Scott Goobie, vice-president of engineering at Bombardier in Toronto. “Spray and his team are second to none in this field of expertise.”

Spray estimates that he is three to five years away from developing new superprotective materials. Still, he feels a sense of urgency to his work, pointing out that Canada and its allies lose far too many soldiers to improvised explosive devices used in conflicts. His goal is to create better armour not only for military vehicles but also for the soldiers themselves, now burdened by heavy, inflexible protective vests.

Firing projectiles out of two large “guns” (one
shown above) at speeds of up to 28,800 kilometres per
hour, John Spray (at left) and his team at the University
of New Brunswick are testing materials that will better
protect soldiers from roadside bombs, astronauts from
hurtling space junk and aircraft from becoming crippled
by bird strikes.

Photo credit: Rob Blanchard/University of New Brunswick

He also hopes to make a difference in the aerospace industry, where birds flying into airplane engines can cause problems. Aircraft manufacturers already have to prove that their planes can withstand a bird strike, but Spray says they often overengineer the safety features, such as the leading edges of wings, to protect them from bird impact. He’s looking for lighter, stronger materials that will do the same job.

The space junk orbiting Earth is threatening satellite systems, which are worth millions of dollars. Even a tiny fragment of a rocket or other debris could obliterate anything in its way, given the speed it travels in orbit. “It is a serious problem, because we use space for our modern society now,” says Spray. “Really, the space realm has become part of the tapestry of our society.”

Spray has his eye on the International Space Station. He is looking for ways to bolster its protective plating, which has to last until 2025, when the station is now expected to be retired.
And when the space station needs refurbishing, Spray sees another need for his work: The kind of armour used in spacesuits is not strong enough to protect astronauts working outside the space station for prolonged periods. “The longer you stay up in space, the more likely you are to be hit,” he says. “It’s a probability game.”
Something the size of a bread crumb hurtling through space at speeds of up to 43,000 kilometres per hour, says Spray, would kill an astronaut. “The suits might be able to stop a grain of sand, but nothing bigger. We need tougher, lighter protective materials for both people and infrastructure in the space regime.”