By Amy Rollins Skywrighter Staff
/ Published March 24, 2017
The Air Force Institute of Technology at Wright-Patterson Air Force Base has been utilizing additive manufacturing, also known as 3D printing, to build prototypes with polymers for more than 30 years. On March 16, its Graduate School of Engineering and Management unveiled a new state-of-the-art metal additive manufacturing system that enables AFIT to digitally fabricate aerospace metal parts. The Concept Laser M2 3D Metal Printer system is a nearly $1 million investment.
Metal additive manufacturing employs a laser to melt a finely graded metal powder, layer by layer, to produce components that are fully dense metal, stated Maj. Ryan O'Hara, assistant professor, Graduate School of Engineering and Management, and AFIT's lead for additive manufacturing.
The finely graded metal powder is carefully contained within the machine and added as needed following a strict protocol that minimizes possible exposure to personnel. The process begins with a build plate on which the part is manufactured. Parts from AFIT's printer may be up to roughly 10 inches by 10 inches by 10 inches or smaller.
After the part is manufactured, the fine metal powder is "sieved, Alaskan gold mine-style," O'Hara said, to remove any small conglomerates and soot and prepare the powder for reuse.
"This is a fairly automated process that is conducted in an isolated and modular system," he said. "Other systems may have a lot more user handling of the powder. We chose this one to limit exposure."
Using this technology, AFIT's research plans will focus on advancing the employment of three primary aerospace metals: inconel - a nickel super alloy titanium and aluminum.
The addition of the new 3D machine allows for AFIT to become an expert in the application of metal additive processes so it is able to make recommendations to the Air Force on the practical implementation of metal additive components for flight-critical air and space applications, O'Hara said.
"Ultimately, this is a capability that enhances the defense focused graduate research that we are already doing, whether that is to produce prototypes faster or get someone into the lab for practical experimentation - those are all things we've traditionally done in polymers to facilitate research and technology applications, and now we're applying these techniques with metal," he said.
The advantage of the metal additive manufacturing system is it can produce internal structures to traditional metal parts that could not normally be machined, according to O'Hara.
"In a recent project, we were able to decrease weight by 10 to 20 percent while increasing stiffness by 20 to 30 percent," he said. "The big advantage there is we can design lighter and stiffer structures that can respond to aerospace environments while delivering greater capabilities."
AFIT has a number of research areas related to additive manufacturing, specifically work on lattice structures, he said. Before the new machine arrived, production of such structures for research had to be outsourced.
"This is a significant investment for us," said Dr. Todd Stewart, AFIT director and chancellor. "We're staying on top of emerging and obviously important technology. I'm excited about that. I understand that this offers somewhat unique capabilities for our Air Force and for our students and faculty."
"This particular machine, in this region, represents the leading edge of additive manufacturing," said Dr. Adedeji Badiru, dean, Graduate School of Engineering and Management. "There are many pockets of additive manufacturing around the Dayton area. We are hoping this new capability will lead to collaboration with the Air Force so we can gain more direct applications."
Dr. Eric Swenson, associate professor, Department of Aeronautics and Astronautics, said the advantage of the 3D printer is it will allow the user to create the one part he or she needs with all the design freedom he or she desires.
"It's a pretty fantastic way to go," he said. "In the long run, it is a lot less expensive. If you find a little problem area, you can fix it and print it again. You can then iterate to a really interesting, fast solution and build spacecraft parts quickly and easily, totally moving the research forward."
"There is so much we can do. It's going to be exciting when we start getting results and being able to publish papers on novel science that no one else has ever done," said Benjamin Doane, a research assistant at the Center for Space Research and Assurance at AFIT. "The possibilities are endless. We can now start printing parts that we can test and compile their data, it is going to be pretty cool."