Military 3D Printing Projects Face Challenges

Unlike the traditional manufacturing process, which creates items by taking raw materials and subtracting from them by drilling or whittling, additive manufacturing takes digital data and creates 3D objects by stacking printed layers of raw materials.

Brennan Hogan, a program manager at LMI — a Virginia-based not-for-profit corporation that is consulting with the Defense Logistics Agency about the implications of 3D printing — said additive manufacturing provides an opportunity for “turning the supply chain on its head.”

Under the traditional supply system, “you create the parts at a manufacturing base and then you send it to a depot, and then it gets put on a component or it gets sent out into the field,” she said during a panel discussion at the Brookings Institution, a Washington, D.C. think tank.

“If you push the entire supply chain forward and you actually put the machine in the field and you’re printing in the field, you’re … truncating the entire process and meeting the need exactly where it is,” she said.

Three-D printing could potentially enable the Defense Department to reduce inventory and storage space, and thereby lower costs, she noted. It could also allow the military to print obsolescent parts that are no longer being manufactured.

As the technology advances, some military leaders want to give 3D printers to depots and deployed troops to facilitate maintenance and operational readiness and save money. The Navy is particularly gung-ho about the technology, having created a “Print the Fleet’” project two years ago to develop procedures for building, qualifying and delivering parts. In recent years, the U.S. military has 3D-printed basic items like oil caps and medical supplies. Going forward, officials envision printing out larger, more complex objects such as aircraft wings or even small drones.

“Soon there will be no physical tether to the supply chain,” Vice Adm. Phillip Cullom, deputy chief of naval operations for fleet readiness and logistics, said at an additive manufacturing conference earlier this year, according to a Navy news release.

But integrating 3D printing into the force on a large scale isn’t as simple as buying the machines and materials and installing them downrange. Many issues and challenges need to be addressed, analysts and industry executives said.

Jim Joyce, a specialist leader at Deloitte Consulting’s manufacturing and operations office, said ensuring quality is the key obstacle.

“What’s that hurdle we have to get over in additive manufacturing before we can unlock the sort of logistical revolution? It’s really part certification,” he said. “If I make a part on my machine, can I replicate that process and all its detail and results on another machine and be sure that I did it [precisely]?”

“Once you crack that code … you really unleash this technology,” he added.

James Kenyon, director of advanced programs and technology at Pratt & Whitney, said industry has concerns about the implications of additive manufacturing when it comes to product manufacturer approval.

“The problem you run into, particularly with aircraft systems, is that there are certain characteristics of those parts that you have to have — its material properties as well as qualities such as surface finish. … If you don’t have them, that part can fail, and when it fails, it will be spectacular and not in a good way,” he said.

“The challenge for us as a manufacturer is that we stand by the quality of our products,” he added. “If you start flying around products that have [3D-printed] parts that we can’t stand by, then it makes it very difficult for us.”

Julie Christodoulou, director of the material science and technology division at the Office of Naval Research, said the service has ongoing initiatives at laboratories and depots to address quality concerns.

“We’re working toward building the confidence in those capabilities and really working to understand how to qualify parts for use,” she told National Defense. “There’s a number of different variables that affect the quality of the component, and we’re spending resources and time to understand how to work with those variations and ultimately predict the capability of the components.”

The Navy hosted an industry day this summer to talk about the service’s additive manufacturing objectives. Christodoulou said a broad agency announcement is expected to be released this fall, soliciting ideas from industry for 3D printing and supporting work to enable part qualifications at military depots.

Efforts to utilize 3D printers on ships could prove more challenging because conditions at sea, such as water vapor and ship movement, make additive manufacturing in such environments more difficult, she said.

At this point, the Navy is having difficulty producing certain types of items with 3D printers, she noted.

“We can pretty well routinely provide mechanical properties that meet or exceed those of a cast product” such as a simple valve, Christodoulou said. “It’s more challenging and indeed at this point impractical to meet properties equivalent to those of a wrought product, one that’s gone through forging or … had some sort of thermal mechanical processing after the casting.”

Technological development isn’t the only issue of concern for those who want to push forward 3D printing. The idea raises intellectual property questions for the Defense Department and industry, analysts noted.

The Pentagon would need to sort through legal issues because it has not licensed the technical rights to many of its acquired end items for decades, Deloitte said in a report last year.

“As a result, the DoD will not be able to adopt [additive manufacturing’s] full promise quickly,” said the report titled, “3D Opportunity in the Department of Defense: Additive Manufacturing Fires Up.”

The Pentagon needs to develop a licensing strategy for computer-aided design (CAD) files and determine the extent to which scanning and reverse engineering can be legally accomplished, the report said.

Troops must also be trained to use 3D printing technology. Forward-deployed end users need to know how to employ CAD files and 3D data and in some cases have engineering knowledge, Hogan said. “There will be a need for having specialists and generalists who can facilitate the process so that the technology can actually be applied.”

While 3D printing could reduce the risk to the U.S. military’s physical supply chain by eliminating the need for parts to be transported, it creates new threats in an age of cyber warfare.

“It’s going to be a digital supply chain, so the military will be sending CAD files to their 3D printers that are forward deployed. Those designs could be manipulated” by a malicious actor, said Jennifer McArdle, a cyber expert at the Center for Revolutionary Thought at the Potomac Institute for Policy Studies.

Navy officials are worried that an adversary could use cyber tools to cause the military to unknowingly print faulty parts for aircraft or other systems.

Troy Johnson, director of the new Navy cyber division within the office of the chief of naval operations, said the service is examining how best to protect 3D printers from direct and indirect attacks. The systems could be vulnerable if they are connected to the Navy’s information networks, or if sailors take a compromised thumb drive and insert it into a 3D printer, he told reporters at the Pentagon. “Those are the areas that we’re concerned about, and those are the areas that we’re working through now as we go.”

The Defense Department will also need to help companies involved in additive manufacturing with cyber security, McArdle said.

“DoD contractors will have to deal with these issues because they are going to be producing systems that the military will be using.”

When it comes to deciding whether to use 3D printing to create a particular item, cost, quality requirements and volume demand are factors that come into play, Christodoulou said.

“It’s not going to be used for everything,” she said. “There is still going to be some components that are just best made by traditional routes. More complex systems certainly are going to be taking advantage of [additive manufacturing technologies] more and more” but “it’s going to come back to the economics of the process and the properties that you want.”

The Defense Department is now on an “evolutionary” rather than revolutionary path when it comes to using 3D printing to facilitate logistics, analysts said.

“The most effective way of applying the technology would be in a modest incremental way” because there are so many complicated aspects to the endeavor, Hogan said. “Our recommendation is that it is …  more of a 10, 15, 20-year timeframe.”

On the industry side, companies also face challenges when it comes to taking full advantage of additive manufacturing to create products.

“Design software needs to take a jump forward before it catches up with the technology,” Joyce said. “There’s a lot of lack of understanding or just frankly, knowledge about how you design the digitally optimal part.”

He compared the current situation to the emergence of composite materials as an alternative to traditional metals in manufacturing.

“There was just an incredible adoption cycle … of getting composite education out to engineering schools before it really flourished,” he said. “That took decades, really.”

Kenyon said Pratt & Whitney has used 3D printing technology to design engine components for the U.S. military, but right now exploiting those tools for design work is “an art,” not a science.

“That’s the real [business] opportunity … because it opens up a whole new way of making things that can cost less because I need less material; that can take less time because I can eliminate some processes out of my manufacturing line,” he said.

Joyce expects 3D printing to propel two different trends in industry.

“You’re going to see the rise of imitative individuals and companies that are producing … obsolete parts and then frankly, going into mainstream parts as we start to sort out what is protected and what isn’t protected legally,” he said.

As the cost of 3D printing machines and materials comes down, “manufacturing increasingly becomes a commodity where folks can just get in. They don’t need as much money. They can set up a very capable machine shop and manufacture things that traditionally were done by very large defense companies.”

On the other hand, opportunities exist for companies to separate themselves from the herd, Joyce said.

“There’s also a group of machines and materials that are becoming highly specialized and regarded as a competitive advantage,” he said. “There’s a limited number of folks, usually with a lot of capital, that are truly differentiating themselves in additive manufacturing.”

Companies pursuing high-end capabilities are building their own additive manufacturing machines, Joyce said. “The machines that are available just aren’t up to snuff.”

Those types of investments have been paying off in the commercial industrial sector, he said. “What we’re seeing so far is it takes a lot of money to lock down the processes on the metal side and create parts. But when you do, you have an advantage over other companies that is significant and justifies that capital investment.”

Christodoulou sees 3D printing as the wave of the future for industry and the Defense Department. “I think it is a longterm trend,” she said. “It’s a very exciting tool that is given to the engineer, and I think that as we begin to understand the capabilities and the limitations it will be used more and more broadly.”

Topics: Manufacturing, Science and Engineering Technology