Electroimpact Inc. would like you to meet SCRAM. The 34-year-old company based in Mukilteo, Washington, near Seattle, has finally pulled back the curtain on its multi-material, multi-process system that can be used to 3D print composite parts without layup mandrels or expensive fixed tooling.
It calls the system Scalable Composite Robotic Additive Manufacturing (SCRAM), and has been working on the technology for more than four years, according to project manager Cody Brown. Only recently, however, did company officials feel comfortable to begin discussing the development publicly. The firm is, at its core, an aerospace company, and has more than 400 engineers on staff out of some 600 total employees.
Electroimpact has integrated a thermoplastic automatic fiber placement (AFP) process and an advanced fused filament fabrication (FFF) 3D printing process to create SCRAM, which it describes as “an industrial, true six-axis, continuous fiber-reinforced 3D printer.”
The process eliminates the need for tooling that is expensive and time-consuming to build, thereby speeding the process to make aerospace-grade, integrated composite structures. The firm uses high-performance thermoplastics –– at the moment, primarily from the family of high-end polyaryletherketone (PAEK) resins –– combined with a high percentage (usually up to 50-60 percent) of continuous fiber reinforcement.
Once the part is fully printed, it is bathed in a vat filled with a solution that dissolves the thermoplastic support material. There is no need for curing, autoclaving, or vacuum bagging.
The result, its officials claim, is a process that can “produce parts with exceptional material properties previously unheard of in the world of additive manufacturing.” It also can produce structures that they claim would otherwise be “geometrically impossible.”
Mechanical engineer and AM specialist Reese Allen stated: “We are also able to use a special FFF process to print a short-fiber-reinforced polymer onto continuous-fiber skin material, which opens up flexibility for things like variable density core (or infill) geometry.”
The current manufacturing configuration involves an enclosed, heated production cell that measures roughly 14 feet in each direction. Electroimpact currently can build a cylindrical part that is about four feet in diameter and five feet tall, said Brown. But the system is “easily scalable and can grow much bigger.” The production cube is insulated and isothermal, since it’s vital to maintain constant temperatures within plus or minus 1 deg. C.
The print time for such a part can range from several days to about a week. But users stand to save weeks, if not months, by being able to eliminate the tool-making step. Electroimpact expects soon to also add milling and drilling capability to the system.
The company has been very deliberate in its pursuit of this project, Brown said. For the first one and a half to two years, “we worked on the fundamental materials and technology research,” trying to learn as much as possible about how best to proceed. They partnered with Siemens’ computer-aided manufacturing group, and have made important advances, in baby steps, in the past two and a half years.
Allen said the team first worked to figure out the material systems. “We did as much engineering as possible on paper, but then you just have to do it.” Electroimpact now is working to further development by collaborating with an aerospace company they declined to identify. It also is talking with several universities, and wants to find “the right one” with which to partner.
“We want to go big, and make strong, integrated, composite structures,” Allen said.
The cost to make each such production unit would be “in the couple million dollar range” now, said Brown. But the plan is to continue development and to bring that cost down substantially.
“Down the road, we hope to be able to sell such systems,” he said, while noting it currently involves a very complex process that requires a substantial learning curve. “It’s not a print and go solution.”
While Electroimpact’s focus is clearly on the aviation and defense industries, company officials potentially see applications in the space program and in automotive, among other sectors.
See the SCRAM in action in this short YouTube video: http://www.electroimpact.com/3d.
The views, opinions and technical analyses presented here are those of the author or advertiser, and are not necessarily those of ULProspector.com or UL Solutions. The appearance of this content in the UL Prospector Knowledge Center does not constitute an endorsement by UL Solutions or its affiliates.
All content is subject to copyright and may not be reproduced without prior authorization from UL Solutions or the content author.
The content has been made available for informational and educational purposes only. While the editors of this site may verify the accuracy of its content from time to time, we assume no responsibility for errors made by the author, editorial staff or any other contributor.
UL Solutions does not make any representations or warranties with respect to the accuracy, applicability, fitness or completeness of the content. UL Solutions does not warrant the performance, effectiveness or applicability of sites listed or linked to in any content.
Really informative article! Hoping to get more related info from your blog!