American defence giant Raytheon is developing a method for the 3D-printing of parts for guided missile weapons using commercially available 3D printers.
The firm’s engineers have already 3D-printed rocket engines and fins, as well as components of the guidance and control system, hoping that in the future the additive manufacturing technology will allow streamlining of the manufacturing processes. Overall, the engineers said, they managed to 3D-print up to 80 per cent of missile components.
“When we print something, we have fewer piece parts, so your supply chain becomes simpler,” said Leah Hull, additive manufacturing manager for Raytheon.
“Your development cycles are shorter; you’re getting parts much faster. You can get a lot more complex with your design because you can design angles you can’t machine into metal.”
The method could be particularly promising for the manufacturing of microscopic electronic circuits and microwave components, used to build sophisticated radars for products including Raytheon’s Patriot air and missile defence system, the firm said.
“The word ‘printing’ implies lower cost,” said Chris McCarroll, director of the Massachusetts Lowell Research Institute at the Raytheon University of Massachusetts.
“It’s additive manufacturing. When we make integrated circuits [now], it’s all subtractive. We put down very expensive materials and wash away everything we don’t need.”
While simple circuits can be printed using existing inkjet printers, 3D-printing would allow more complicated designs, higher resolution and performance, the researcher believes.
Raytheon’s material expert Teresa Clement envisions that, in the future, instead of building separate parts and then assembling them, engineers could 3D-print complex systems in one go.
“There’s currently a hierarchy in our manufacturing. We make the structures, the housings, the circuit cards, with the right materials, and then we integrate them into a system,” she said. “What we see in the near future is printing the electronics and printing the structures, but still integrating. Eventually, we want to print everything together.”
Engineers at the research institute are already able to lay down the conductors and dielectrics needed for printed electronics. They can even lay down carbon nanotubes and are working to align them to build futuristic circuits.
Even though it is already possible to 3D-print up to 80 per cent of missile components, the researchers say that for the troops to be able to print the weaponry in the field, a lot remains to be accomplished.
“Before a war fighter can print a missile in the field, you need quality-controlled processes to fabricate all the component materials: the metallic strongbacks and the plastic connectors, the semiconductors for processors, and the energetics and propulsion systems,” explained McCarroll.
“The hard part is then making the connections between these components: as an example, the integrated control circuit that receives the command to light the fuse. At some relatively near-term point you may have to place chips down and interconnect them with printing. Or, in the future, maybe you’ll just print them.”