Additive manufacturing, including emerging “3D printing” technologies, is booming. Last year an astronaut on the International Space Station used a 3D printer to make a socket wrench in space, hinting at a future when digital code will replace the need to launch specialized tools into orbit. Here on Earth, the Navy is considering applications for additive manufacturing aboard ships, and a commercial aircraft engine company recently announced its first FAA-approved 3D-printed part. Despite its revolutionary promise, however, additive manufacturing is still in its infancy when it comes to understanding the impact of subtle differences in manufacturing methods on the properties and capabilities of resulting materials. Overcoming this shortcoming is necessary to enable reliable mass production of additively manufactured structures such as aircraft wings or other complex components of military systems, which must meet demanding specification requirements.
The Defense Advanced Research Projects Agency’s (DARPA) Open Manufacturing program seeks to solve this problem by building and demonstrating rapid qualification technologies that comprehensively capture, analyze and control variability in the manufacturing process to predict the properties of resulting products. Success could help unleash the potential time- and cost-saving benefits of advanced manufacturing methods for a broad range of defense and national security needs.
“The Open Manufacturing program is fundamentally about capturing and understanding the physics and process parameters of additive and other novel production concepts, so we can rapidly predict with high confidence how the finished part will perform,” said Mick Maher, program manager in DARPA’s Defense Sciences Office. “The reliability and run-to-run variability of new manufacturing techniques are always uncertain at first, and as a result we qualify these materials and processes using a blunt and repetitive ‘test and retest’ approach that is inevitably expensive and time-consuming, ultimately undermining incentives for innovation.”
To achieve enhanced manufacturing control, Open Manufacturing is investigating rapid qualification technologies that could be applied not just to additive manufacturing but to any of a range of potentially new manufacturing methodologies. The program comprises three efforts—two focusing on metal additive processes and one on bonded composite structures:
- The Rapid Low Cost Additive Manufacturing (RLCAM) effort aims to use first-principles and physics-based modeling to predict materials performance for direct metal laser sintering (DMLS) using a nickel-based super alloy powder. In DMLS a laser melts the metal powder to additively build a 3D product.
- The Titanium Fabrication (tiFAB) effort aims to combine physics- and data-based informatics models to determine key parameters that affect the quality of large manufactured structures, such as aircraft wings. tiFAB is a method that uses an electron beam instead of a laser to melt spool-fed titanium wire to build up a structure layer by layer.