PICATINNY ARSENAL, N.J.: To the ordinary person, it may seem like nothing more than a simple powder. To engineers here at the Armament Research, Development and Engineering Center, this tiny substance has the potential to do some extra-ordinary things for warfighters.
From the tanks they drive, to the armor they wear, to the ammunition they fire — the “nano” powders developed by ARDEC’s nanotechnology team can have practical applications in nearly every part of the Soldier’s inventory.
“Nano-powders produced by the ARDEC team exhibit unique chemical, physical and mechanical properties that far exceed the capabilities of conventional materials,” said Joseph Paras, materials engineer.
These improved nano-properties include reduced weight, higher strength, increased durability, increased reactivity, and the ability to vary or “tune” certain properties. These properties allow for great potential when it comes to reducing the weight of Soldier equipment and improving lethality and survivability.
This cutting-edge nanotechnology has been under way at ARDEC for the last 10 years, and so far has shown significant progress. In fact, ARDEC’s nanotechnology lab is the largest facility in North America to produce nano-scale powders and materials.
Nano Warfighter Applications
Nano-powders can be heated and molded to a variety of shapes and sizes, such as coils or plates, which can be applied to a wide range of products like novel explosives, warheads and countermeasure flares.
One example is using nano-materials to develop novel lightweight composites that could serve as alternatives to traditional steel.
“The Army uses a lot of steel — and steel is heavy,” Paras said. “There is a big push across the Army and the Department of Defense to find a lighter alternative. We’re using nanotechnology to combine aluminum and other materials to enhance the strength, so that it can compete with the performance of steel.”
One such nano-composite material is one-third the weight of steel, which can have a monumental impact if applied to the Army’s tanks and other combat vehicles.
“It would greatly reduce fuel costs, as well as ease the burden for logistics. There are many varieties of steel, so we’d have to do the same kind of tailoring for this material,” Paras said.
Nano-materials can also have practical applications in the Soldier’s armor, as strong bonds formed by the nano-particles can greatly increase multi-hit capability.
They also have applications in a variety of energetics, or explosives. “By making aluminum on the nano-scale, we change/increase the available surface area so it can potentially burn spontaneously as soon as it hits the air, making it more reactive,” Paras said. “When using a nano-scale energetic, it’s possible to increase the yield over traditional explosives.”
One success story in using nanotechnology in energetics is a nano-iron material that is now being explored as an alternate source for use in the M211 flares.
The closest of these nano-products to be fielded is “Green Primer” which is essentially a lead-free primer for ammunition.
“The primer is what sets off the gun powder — and though the Army has removed lead from the bullets themselves, there’s still some lead azide in the primer,” said Darold Martin, senior engineer at the Particulate Materials Lab. “The nano-version of this substance is much safer and much less toxic. It could be used in a range of munitions.”
“When we look at materials on a nano level, we’re looking at ultrafine particles that are on the order of one-billionth of a meter in diameter,” Paras said. “It gives us tremendous ability to change the way these materials normally work, due to the extraordinary phenomena that happen when you go to the nano scale.”
Nano-structured powders are created when a combination of materials are continuously crushed using a high-energy grinding process, called milling.
“We’re basically taking conventional substances like aluminum or magnesium, and we’re continuously breaking them up in the milling machine and reshaping them into a very fine, lamellar nano-structure,” Paras said. “By reducing the grain size, you can greatly enhance the properties of the metal.”
In addition to making nano-composite powders, the team can also create nano-structures from scratch, using an advanced vaporizing and cooling process.
“We take raw aluminum and melt it using extremely high-temperature plasma, so it turns into its vapor state,” Paras said. “Then we “quench” it — which means we cool it down very rapidly to condense out very tiny particles. It’s similar to water condensing on the outside of a cool glass, except we cool so fast, the vapor instantaneously becomes a solid. Then, we can extract the nano-particles and harvest them for use in a wide array of applications.”
Why Nano, Why now?
Many consider nanotechnology to be a relatively new field, emerging in the scientific community about 20 years ago. However, the early origins of the science stem back to medieval times, when artisans crushed clay particles to create a glittery glaze on their pottery.
“The theories behind nano-science have always been there, but being able to make the materials and put them into a useful configuration — that kind of technology and equipment hasn’t been there until recently,” Martin said. “We take theory from universities or small businesses that do the research, and we transition them into promising technologies.”
The ARDEC is at the forefront of nanotechnology, even within private industry. In fact, Martin noted that many industry partners provide funding to ARDEC to continue research in the nano field.
As with any new technology, keeping the product at a reasonable cost is always a challenge.
“It’s such a new technology, so we can’t bring the manufacturing costs down yet. We have to re-tool our facilities to be able to mass produce a lot of this stuff,” Martin said.
“If it was easy, it would be done already,” he added. “It’s sort of like baking, in that there is an art to it, you can’t always tell why certain things work exactly right together, but when they do, you know it.”
So while ARDEC scientists continue to develop new nano-powders and materials, while finding cost-effective ways to carry them forward, the long-term goal is to bring more capability to the warfighter.
“We’re working on emerging technology that is basically trying to enhance the lethality in the hand of the Soldier and the survivability of the Soldier,” said Deepak Kapoor, nano-materials team lead.
“If you can provide him better performing materials that can help him live longer, survive longer, and kill longer — that is what any new technology is trying to capture right now.”