Major US aerospace and defence group Northrop Grumman has reported that it has made a significant advance in the additive manufacturing (AM, also called 3D printing) production of carbon/carbon composite materials for use in high-temperature aerospace and defence applications. Northrop Grumman’s process is allowing the company to AM continuous fibre composites at a large scale, which it says is “unprecedented’ in AM.

“We are pioneering a rapid fabrication process that does not require tooling to manufacture aerospace-grade, continuous fibre integrated composite structures,” stated Northrop Grumman Weapon Systems VP and GM Dan Olson. “This manufacturing advancement will deliver capability to the field much faster than traditional methods, and ensures our warfighters have the latest technology and advanced weapons to counter both existing and future threats.”

The technology developed by the group has been designated Scalable Composite Additive Manufacturing (SCRAM). This is a true six-axis continuous fibre industrial AM machine (also known as a 3D printer). This is used to produce integrated composite structures. These are then subjected to a proprietary manufacturing process, to be converted into carbon/carbon structures.

These carbon/carbon structures are complex and come out of the manufacturing process in their almost final required shapes – near-net shape is the industrial term. Such heat-resistant complex shapes are needed by Northrop Grumman to create hypersonic and other high-speed weapons.

The group has secured multiple patents with SCRAM. This technology does not need long-lead tooling and includes the in-situ consolidation of the composites. This “dramatically changes the cost paradigm” for the production of high-temperature composites, the company affirmed.

Further, while previously carbon/carbon manufacturing techniques were labour intensive, SCRAM reduces production costs and time by up to 50% by the use of process automation. Moreover, process automation has delivered a measurable improvement in the consistency and quality of the components produced.

“AM has the potential to improve the agility of aerospace manufacturers where legacy casting and forging processes are often resource and time intensive; it is a leading-edge production technology that is foundational to US global competitiveness and manufacturing resiliency,” asserted the group.