After a little more than a year of research and more than 20 attempts to get the right materials, an Air Force Academy cadet and a professor at the school have developed a kind of goo that can be used to enhance existing types of body armor.
As part of a chemistry class project in 2014, Cadet 1st Class Hayley Weir was assigned epoxy, Kevlar, and carbon fiber to use to create a material that could stop a bullet.
The project grabbed Weir’s interest. “Like Under Armour, for real,” she said.
The materials reminded her of Oobleck, a non-Newtonian fluid — which thickens when force is applied — made of cornstarch and water and named after a substance from a Dr. Seuss book, and she became interested in producing a material that would stop bullets without shattering. An adviser suggested swapping in a thickening fluid for the epoxy, which hardened when it dried.
” Up to that point, it was the coolest thing I’d done as a cadet,” Weir, set to graduate this spring, told Air Force Times.
But soon thereafter she had to switch majors from materials chemistry to military strategies. That presented a challenge to continuing the research, but she eventually teamed up with Ryan Burke, a military and strategic studies professor at the Academy.
Burke, who served as a Marine, was familiar with the cumbersome nature of current body armor, and he was enthused about Weir’s project. “When she came to me with this idea, I said ‘let’s do it,'” he said. “Even if it is a miserable failure, I was interested in trying.”
The science behind the material is not new, and Burke expected the vast defense industry to have pursued such a substance already. But a search through previous studies found no such work, and researchers and chemists at the Air Force Civil Engineer Center said the idea was worth looking into.
They began work during the latter half of 2016 using the Academy’s firing range, weapons, and a high-speed camera. Burke got in touch with Marine Corps contacts who provided testing materials.
In the lab, Weir would make the mixture using a KitchenAid mixer and plastic utensils. It would then be placed in vacuum-sealed bags, flattened into quarter-inch layers, and inserted into a swatch of Kevlar.
At first, during tests with a 9 mm pistol, they made little headway.
“Bullets kept going straight through the material with little sign of stopping,” Weir told Air Force Times. After revisiting their work and redoing the layering pattern, they returned to the firing range on December 9.
Apprehensive, Weir fired on the material.
“Hayley, I think it stopped it,” Burke said after reviewing the video. It was the first time their material had stopped a bullet.
This year, they traveled to the Air Force Civil Engineering Center to present their work and up the ante on their tests.
Weir’s material was able to stop a 9 mm round, a .40 Smith & Wesson round, and eventually a .44 Magnum round — all fired at close range.
During the tests, 9 mm rounds went through most the material’s layers before getting caught in the fiber backing. The .40 caliber round was stopped by the third layer, while the .44 Magnum round was stopped by the first layer.
The .44 Magnum round — which has been used to hunt elephants — is “a gigantic bullet,” Weir told Air Force Times. “This is the highest caliber we have stopped so far.” Because it could stop that round, the material could be certified as type 3 body armor, which is usually worn by Air Force security personnel.
The harder the impact from the bullet, the more the molecules in the material responded, yielding better resistance. “The greater the force, the greater the hardening or thickening effect,” Burke said.
“We’re very pleased,” said Dr. Jeff Owens, a senior research chemist with the Air Force Civil Engineering Center’s requirements, research, and development division. “We now understand more about what the important variables are, so now we’re going to go back and pick all the variables apart, optimize each one, and see if we can get up to a higher level of protection.”
The model Weir and Burke created uses 75% less fabric than standard military-style body armor.
It also has the potential for use as a protective lining on vehicles and aircraft and in tents that would protect their occupants from shrapnel or gunfire.
“It’s going to make a difference for Marines in the field,” Burke said.
On the civilian side, the material could aid emergency responders in active-shooter situations.
“I don’t think it has actually set in how big this can get,” Weir said in early May. “I think this is going to take off and it’s going to be really awesome.”
While the ultimate use of the material remains to be seen, the US Army and Marine Corps are reportedly looking for ways lighten the body armor their personnel are currently using.
A study by the Government Accountability Office, noted by Army Times, highlighted joint efforts to lower the weight of current body armor, which on average weighs 27 pounds. Including body armor, the average total weight carried by Marines is 117 pounds, while soldiers are saddled with 119 pounds, according to the report.
The Army and Marines have looked into several ways to redistribute the weight currently carried by soldiers and Marines, including new ways to transport their gear on and around the battlefield. The GAO report also noted that both branches made updates to soft armor, in some cases cutting 6 to 7 pounds.