Last year, ITAMCO (Indiana Technology and Manufacturing Companies), which focuses on exploring alternatives to traditional production processes, teamed up with researchers from Purdue University in order to create a 3D printed version of an airport runway mat for the United States Air Force to use in temporary or expeditionary flight operations.
After winning funding for Phase I of the competitive SBIR (Small Business Innovation Research) program, the team was able to compete for Phase II project funding for the 3D printed runway mat, and announced that it has been awarded this funding.
Small businesses based in the US are encouraged to work on Federal Research / Research and Development as part of the SBIR program, with possible commercialization as the end goal. ITAMCO has been providing open gearing and precision machining services to heavy-duty industries since 1955, and launched a successful “Strategic Technology Initiative for Additive Manufacturing” back in 2015. ITAMCO and its partners confirmed the commercial potential, feasibility, and technical merit of the 3D printed runway mat for Phase I, but Phase II will see the team moving on to the prototype and testing processes.
We often hear the term “readiness” used when discussing military objectives, which measures the ability of a unit to accomplish its mission. Since the Vietnam War, the US military has been most often using a portable runway surface made with AM-2, an aluminum plank matting. While this has been doing the trick for decades, the Air Force believes it’s time for an upgrade, and ITAMCO’s research project team is ready to deliver.
The team’s research objective has been to create an alternative to the AM-2 runway mat using strong roll, or sheet, technology, and additive manufacturing will provide multiple benefits in this endeavor. Portable airway mats need to be strong enough to hold up under many aircraft takeoffs and landings, but still easy to store and set up. Working with Pablo Zavattieri, an Associate Professor with Purdue’s Lyles School of Civil Engineering, the team has proposed a solution that features an upper surface, which will match up with the lower surface, and uses Phase Transforming Cellular Matrix (PXCM) geometry to help with the loading and shear stresses the mat will have to withstand.
Professor Zavattieri explained, “The main advantage is that not only can it be used as an energy-absorbing material but unlike many other materials designed for this purpose, the PXCMs would be reusable because there is no irreversible deformation.”
Items that are made using PXCM geometry can actually change from one stable configuration to another, and then back again. So, in essence, the ITAMCO team’s 3D printed runway mat should be able to “heal” itself, which definitely increases the product’s lifespan. In fact, according to a 2016 article published by ASME regarding PXCMs developed by Purdue and General Motors, they can be “scaled to almost any size and 3D printed,” and can also “perform similarly to commercial metallic cellular structures used for energy dissipation without relying on plastic deformation.”
ITAMCO and Purdue are also using Sunata by Atlas 3D, a cloud-based, ITAR-compliant software that’s used by multiple Fortune 500 companies and the Department of Defense. The software selects the best orientation for 3D prints, and will automatically generate necessary support structures. The new 3D printable PXCM material being used to make the runway mat can support flight operations of 5,000 landing and takeoff cycles over 60 days, and can be laid on a level surface of the proper density by hand. In addition, the runway’s performance will not be negatively impacted by debris.
The new PXCM solution is targeted to weigh 3.5 lbs per sq ft or less, and prototypes of the runway mat will be 3D printed on ITAMCO’s EOS M290 system. The team will be testing the new 3D printed prototypes against the MIL-Spec for the existing AM-2 runway mat, as well as preparation of the final repair site and the mat’s ability to restore itself to the original shape and function, with full operational capability, 30 minutes post-compaction.